1987 JEEP : TPS Question

[k***@earthlink.net]

1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.

Where does the Throttle Position Sensor input voltage come from?

I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.

My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.

I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.

Any advice is welcomed, thanks.

[Will Honea]

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.

The factory manual for the Renix system (same as my '88 Commanche) says that
the reference voltage should be 5.0 volts supplied by the computer but
yours may be running slightly differently. My adjustment procedure (from
the manual) is .86 volts ouput with the throttle at dead idle to 4.95 at
WOT. If it is the 5.0 reference, you'll also find that the MAP sensor
supply is high. If that's the case, good luck finding another computer!
As I recall, the Rennix system was only used in 87 and 88 - maybe a few of
early the 89's had it butthe 90's on used the MOPAR unit. That had totally
different sensors and was set up for the HO engine with different intake
manifolds and headers along with a reworked head. If the engine runs OK
beyond the idle/WOT performance, you might be able to repair the voltage
reference inside the computer but that's chancy - I've never gotten the
schematics for that beast.

[bllsht]

Post by Will Honea

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.

The factory manual for the Renix system (same as my '88 Commanche) says that
the reference voltage should be 5.0 volts supplied by the computer but
yours may be running slightly differently. My adjustment procedure (from
the manual) is .86 volts ouput with the throttle at dead idle to 4.95 at
WOT. If it is the 5.0 reference, you'll also find that the MAP sensor
supply is high. If that's the case, good luck finding another computer!
As I recall, the Rennix system was only used in 87 and 88 - maybe a few of
early the 89's had it butthe 90's on used the MOPAR unit. That had totally
different sensors and was set up for the HO engine with different intake
manifolds and headers along with a reworked head. If the engine runs OK
beyond the idle/WOT performance, you might be able to repair the voltage
reference inside the computer but that's chancy - I've never gotten the
schematics for that beast.

Renix was 87 - 90. Mopar from 91 on.

[Will Honea]

Renix was 87 - 90.  Mopar from 91 on.

I thought the 90's were Mopar - so much for memory. I got the same advice
from the Jeep dealer about soldering those splices, BTW.

My guess would be that the computer is OK and the OP has connection
problems. I also had to clean that bulkhead connector to get mine to idle
right when I first got it. That was part of a 3 month process of cleaning
ports and connectors to get it all done - seems like every connector in the
engine bay was dirty/corroded and every port in the throttle body at least
partially blocked. Eight years later it's looking like I need to repeat
the process myself.

[k***@earthlink.net]

Bill Hughes, Will, & Bllsht,

Thank each of you for responding.

When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.

My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.

The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).

I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.

I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).

Each time the transmission would randomly go ignorant, I'd checked the
TPS. Each time it reported in @ 83ish% --until September. Once I
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.

I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.

Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.

Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

Any Suggestions?
Thanks,
Ken

Post by Will Honea

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.

The factory manual for the Renix system (same as my '88 Commanche) says that
the reference voltage should be 5.0 volts supplied by the computer but
yours may be running slightly differently. My adjustment procedure (from
the manual) is .86 volts ouput with the throttle at dead idle to 4.95 at
WOT. If it is the 5.0 reference, you'll also find that the MAP sensor
supply is high. If that's the case, good luck finding another computer!
As I recall, the Rennix system was only used in 87 and 88 - maybe a few of
early the 89's had it butthe 90's on used the MOPAR unit. That had totally
different sensors and was set up for the HO engine with different intake
manifolds and headers along with a reworked head. If the engine runs OK
beyond the idle/WOT performance, you might be able to repair the voltage
reference inside the computer but that's chancy - I've never gotten the
schematics for that beast.

[Will Honea]

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.
Any Suggestions?
Thanks,
Ken

Post by Will Honea

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.

The factory manual for the Renix system (same as my '88 Commanche) says
that the reference voltage should be 5.0 volts supplied by the computer
but
yours may be running slightly differently. My adjustment procedure (from
the manual) is .86 volts ouput with the throttle at dead idle to 4.95 at
WOT. If it is the 5.0 reference, you'll also find that the MAP sensor
supply is high. If that's the case, good luck finding another computer!
As I recall, the Rennix system was only used in 87 and 88 - maybe a few of
early the 89's had it butthe 90's on used the MOPAR unit. That had
totally different sensors and was set up for the HO engine with different
intake
manifolds and headers along with a reworked head. If the engine runs OK
beyond the idle/WOT performance, you might be able to repair the voltage
reference inside the computer but that's chancy - I've never gotten the
schematics for that beast.

At 276k on the clock, the whole power train is tired and the tranny has all
sorts of worn parts, so I pass on that. For the idle, just unplug the TPS
(both of them) and clean the plug contacts with contact cleaner.

[PeterD]

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

When you put a scan tool on it, what DTCs do you get?

[Jeff Strickland]

Post by PeterD

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

When you put a scan tool on it, what DTCs do you get?

It's an '87, not '97. There is no scan tool to pull DTCs.

[dave AKA vwdoc1]

FYI
The Bendix Jeep Tester will get you those codes on an '87 and on my '88.
I have the manual with all of the codes.
I sent those codes to the Renix group on Yahoo after scanning them
http://autos.groups.yahoo.com/group/RENIXPower
but I don't think that they were grouped & posted in a file yet.

The Tester also allows you to see what the ECM sees, TPS position, CTS
temperature, etc.
--
later,
dave AKA vwdoc1
88 XJ 4.0 auto
snip

Post by Jeff Strickland

Post by PeterD
When you put a scan tool on it, what DTCs do you get?

It's an '87, not '97. There is no scan tool to pull DTCs.

[Jeff Strickland]

Or, you can cycle the key OFF/ON five times and the Check light will blink
the codes.

Post by dave AKA vwdoc1
FYI
The Bendix Jeep Tester will get you those codes on an '87 and on my '88.
I have the manual with all of the codes.
I sent those codes to the Renix group on Yahoo after scanning them
http://autos.groups.yahoo.com/group/RENIXPower
but I don't think that they were grouped & posted in a file yet.
The Tester also allows you to see what the ECM sees, TPS position, CTS
temperature, etc.
--
later,
dave AKA vwdoc1
88 XJ 4.0 auto
snip

Post by Jeff Strickland

Post by PeterD
When you put a scan tool on it, what DTCs do you get?

It's an '87, not '97. There is no scan tool to pull DTCs.

[dave AKA vwdoc1]

Not on the Renix system AFAIK.
I think the 1991-1995 "Chrysler" OBD-I might have the blinking system. ;-)

Post by Jeff Strickland
Or, you can cycle the key OFF/ON five times and the Check light will blink
the codes.

Post by dave AKA vwdoc1
FYI
The Bendix Jeep Tester will get you those codes on an '87 and on my '88.
I have the manual with all of the codes.
I sent those codes to the Renix group on Yahoo after scanning them
http://autos.groups.yahoo.com/group/RENIXPower
but I don't think that they were grouped & posted in a file yet.
The Tester also allows you to see what the ECM sees, TPS position, CTS
temperature, etc.
--
later,
dave AKA vwdoc1
88 XJ 4.0 auto
snip

Post by Jeff Strickland

Post by PeterD
When you put a scan tool on it, what DTCs do you get?

It's an '87, not '97. There is no scan tool to pull DTCs.

[bllsht]

The Renix ECU doesn't store DTCs. The tester you refer to (MS 1700)
will guide you through a self test (key on, key off, step on
accelerator, etc) and look for the proper response. If it doesn't see
what it expects, it'll give you a code to look up a diagnostic
procedure. Useful if you have a dead sensor, but no help if your
problem is intermittent or a sensor that's just slightly off. The most
useful thing is the serial data readout which lets you see sensor
values in real time, but only one sensor at a time.

This tool was replaced by the Jeep/Eagle adapter used with the DRBII.



On Thu, 29 Oct 2009 21:38:44 -0500, "dave AKA vwdoc1"

Post by dave AKA vwdoc1
FYI
The Bendix Jeep Tester will get you those codes on an '87 and on my '88.
I have the manual with all of the codes.
I sent those codes to the Renix group on Yahoo after scanning them
http://autos.groups.yahoo.com/group/RENIXPower
but I don't think that they were grouped & posted in a file yet.
The Tester also allows you to see what the ECM sees, TPS position, CTS
temperature, etc.

[Will Honea]

That serial stream is what I'm really most interested in. Any suggestions
on where to find out the specifics of the interface? I fiddled with it and
got the stream to display from a serial port connected via an optical
isolator (I don't trust anyone's implementation!) - can't recall all the
details, but it was pretty straight forward to that point. Of course, I
had no idea of what it meant but I could get a predictable stream. The
interpretation and control codes are what I'm looking for.

Post by bllsht
The Renix ECU doesn't store DTCs. The tester you refer to (MS 1700)
will guide you through a self test (key on, key off, step on
accelerator, etc) and look for the proper response. If it doesn't see
what it expects, it'll give you a code to look up a diagnostic
procedure. Useful if you have a dead sensor, but no help if your
problem is intermittent or a sensor that's just slightly off. The most
useful thing is the serial data readout which lets you see sensor
values in real time, but only one sensor at a time.
This tool was replaced by the Jeep/Eagle adapter used with the DRBII.
On Thu, 29 Oct 2009 21:38:44 -0500, "dave AKA vwdoc1"

Post by dave AKA vwdoc1
FYI
The Bendix Jeep Tester will get you those codes on an '87 and on my '88.
I have the manual with all of the codes.
I sent those codes to the Renix group on Yahoo after scanning them
http://autos.groups.yahoo.com/group/RENIXPower
but I don't think that they were grouped & posted in a file yet.
The Tester also allows you to see what the ECM sees, TPS position, CTS
temperature, etc.

[DougW]

Post by Will Honea
That serial stream is what I'm really most interested in. Any
suggestions on where to find out the specifics of the interface? I
fiddled with it and got the stream to display from a serial port
connected via an optical isolator (I don't trust anyone's
implementation!) - can't recall all the details, but it was pretty
straight forward to that point. Of course, I had no idea of what it
meant but I could get a predictable stream. The interpretation and
control codes are what I'm looking for.

Might try digging here.
http://www.obd2allinone.com/sc/pages.asp?pageid=60

I'm seeing some things I might try with my ZJ.

[dave AKA vwdoc1]

Thanks bllsht for elaborating on the MS 1700! ;-)

The RenixPower group has some people working on making some interface if you
can't or don't want to buy the MS 1700 or Snap-On MT2500 or another
compatable scanner/reader/tester.
http://autos.groups.yahoo.com/group/RENIXPower
Not sure how far they have gotten, but you can collaborate with them. ;-)
--
later,
dave AKA vwdoc1
88 XJ 4.0 auto

Post by Will Honea
That serial stream is what I'm really most interested in. Any suggestions
on where to find out the specifics of the interface? I fiddled with it and
got the stream to display from a serial port connected via an optical
isolator (I don't trust anyone's implementation!) - can't recall all the
details, but it was pretty straight forward to that point. Of course, I
had no idea of what it meant but I could get a predictable stream. The
interpretation and control codes are what I'm looking for.

Post by bllsht
The Renix ECU doesn't store DTCs. The tester you refer to (MS 1700)
will guide you through a self test (key on, key off, step on
accelerator, etc) and look for the proper response. If it doesn't see
what it expects, it'll give you a code to look up a diagnostic
procedure. Useful if you have a dead sensor, but no help if your
problem is intermittent or a sensor that's just slightly off. The most
useful thing is the serial data readout which lets you see sensor
values in real time, but only one sensor at a time.
This tool was replaced by the Jeep/Eagle adapter used with the DRBII.
On Thu, 29 Oct 2009 21:38:44 -0500, "dave AKA vwdoc1"

Post by dave AKA vwdoc1
FYI
The Bendix Jeep Tester will get you those codes on an '87 and on my '88.
I have the manual with all of the codes.
I sent those codes to the Renix group on Yahoo after scanning them
http://autos.groups.yahoo.com/group/RENIXPower
but I don't think that they were grouped & posted in a file yet.
The Tester also allows you to see what the ECM sees, TPS position, CTS
temperature, etc.

[Will Honea]

Post by dave AKA vwdoc1
Thanks bllsht for elaborating on the MS 1700! ;-)
The RenixPower group has some people working on making some interface if
you can't or don't want to buy the MS 1700 or Snap-On MT2500 or another
compatable scanner/reader/tester.
http://autos.groups.yahoo.com/group/RENIXPower
Not sure how far they have gotten, but you can collaborate with them. ;-)

That's where I got interested in this again. I really need to find someone
with MS 1700 so I can monitor the exchanges between it and the computer. I
can read the stream but interpreting it with what I've found so far is a
real project without a better map than I have at this point.

[Mike Romain]

Post by Will Honea

Post by dave AKA vwdoc1
Thanks bllsht for elaborating on the MS 1700! ;-)
The RenixPower group has some people working on making some interface if
you can't or don't want to buy the MS 1700 or Snap-On MT2500 or another
compatable scanner/reader/tester.
http://autos.groups.yahoo.com/group/RENIXPower
Not sure how far they have gotten, but you can collaborate with them. ;-)

That's where I got interested in this again. I really need to find someone
with MS 1700 so I can monitor the exchanges between it and the computer. I
can read the stream but interpreting it with what I've found so far is a
real project without a better map than I have at this point.

I think I have the 87 FSM kicking around in PDF format, would that help
and how could I get it to you.

Mike
2000 Cherokee Sport
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00
'New' frame and everything else in '09. Some Canadian Bush Trip and
Build Photos: http://mikeromainjeeptrips.shutterfly.com

[Will Honea]

Post by Mike Romain

Post by Will Honea

Post by dave AKA vwdoc1
Thanks bllsht for elaborating on the MS 1700! ;-)
The RenixPower group has some people working on making some interface if
you can't or don't want to buy the MS 1700 or Snap-On MT2500 or another
compatable scanner/reader/tester.
http://autos.groups.yahoo.com/group/RENIXPower
Not sure how far they have gotten, but you can collaborate with them.
;-)

That's where I got interested in this again. I really need to find someone
with MS 1700 so I can monitor the exchanges between it and the computer.
I can read the stream but interpreting it with what I've found so far is
a real project without a better map than I have at this point.

I think I have the 87 FSM kicking around in PDF format, would that help
and how could I get it to you.
Mike
2000 Cherokee Sport
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00
'New' frame and everything else in '09. Some Canadian Bush Trip and
Build Photos: http://mikeromainjeeptrips.shutterfly.com

Thanks, Mike. I already have the full FSM on the shelf. It says
diddly-squat about ECU diagnostics - doesn't really say anything about the
MS 1700 or how it is used. Gives a lot of grease monkey info about the
engine components but nothing beyond that.

[k***@earthlink.net]

PeterD,
I do not own a mt2500, but I found someone who had one. We were not able
to get any specific codes from the ecu or the tcu, but all of the basic
reporting features illustrated nominal/pass results. I heard it said
that a DRB II would do nicely but no shop in the city has one. I have
the Renix ECU made by Bendix (replaced with a new one 2 years ago).

What do you think?
Ken

Post by PeterD

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

When you put a scan tool on it, what DTCs do you get?

[PeterD]

Post by k***@earthlink.net
PeterD,
I do not own a mt2500, but I found someone who had one. We were not able
to get any specific codes from the ecu or the tcu, but all of the basic
reporting features illustrated nominal/pass results. I heard it said
that a DRB II would do nicely but no shop in the city has one. I have
the Renix ECU made by Bendix (replaced with a new one 2 years ago).
What do you think?
Ken

Some ECU/TCUs will inhibit overdrive if there are codes, but that
doesn't seem to be the problem. I'm not sure what's up at this stage.

[Jeff Strickland]

Post by PeterD

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

When you put a scan tool on it, what DTCs do you get?

It's an '87, not '97. There is no scan tool to pull DTCs.

[k***@gmail.com]

Do you have insight as to why the engine would reeve up in conditions of
cool weather - clod starts?
Thanks,
Ken

Post by PeterD

Bill Hughes, Will,& Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear&
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open& look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

When you put a scan tool on it, what DTCs do you get?

[PeterD]

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.

When you put a scan tool on it, what DTCs do you get?

[Will Honea]

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.
Any Suggestions?
Thanks,
Ken

Post by Will Honea

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.

The factory manual for the Renix system (same as my '88 Commanche) says
that the reference voltage should be 5.0 volts supplied by the computer
but
yours may be running slightly differently. My adjustment procedure (from
the manual) is .86 volts ouput with the throttle at dead idle to 4.95 at
WOT. If it is the 5.0 reference, you'll also find that the MAP sensor
supply is high. If that's the case, good luck finding another computer!
As I recall, the Rennix system was only used in 87 and 88 - maybe a few of
early the 89's had it butthe 90's on used the MOPAR unit. That had
totally different sensors and was set up for the HO engine with different
intake
manifolds and headers along with a reworked head. If the engine runs OK
beyond the idle/WOT performance, you might be able to repair the voltage
reference inside the computer but that's chancy - I've never gotten the
schematics for that beast.

At 276k on the clock, the whole power train is tired and the tranny has all
sorts of worn parts, so I pass on that. For the idle, just unplug the TPS
(both of them) and clean the plug contacts with contact cleaner.

[k***@earthlink.net]

Since 10/2009, just wanted to follow up and update on the TPS issue.

I was sure my transmission was an electrical issue, and not a mechanical
one. The TPS seemed to be a part of that premise. In the summer 0f 2010,
after driving without overdrive for a year, I pulled into a sleeply
little town in Mississippi (Pascagoula) and a home grown auto repair
shop. Ole boy said his modis scanner said my brake was depresssed. ---
Overdrive solved by replacing a burnt wire under dash near pedals. Just
saved $2,300 for what 10 authorized mechanics wanted to charge.

Well, it's winter time again and my jeep is following it's attitude as
in the past 5 winters. Cold temperature (35 to 45 degrees) it reeves
over 3500 rpms the first time starting it in the morning. I have to shut
off, and restart no less than 4 times before the reeving of the engine
subsides. Any suggestions? EGR? vacuum? relay?

Your input has been and is appreciated,
Ken

Post by k***@earthlink.net
Bill Hughes, Will, & Bllsht,
Thank each of you for responding.
When I posted the message, I decided to jump into the jeep and go
purchase a new TPS as a last ditch effort when I considered the other
possible costs.
My initial symptoms started ALL at once, back in May this year. While
driving on the interstate, the transmission when out (save 1st gear &
some second). Low fluid. So I immediately added enough fluid to get home.
The transmission wouldn't work properly and also started having engine
idle problems (cold start kills, and also at running temperature having
very high idles).
I dropped the pan, changed the screen, cleaned the magnet (slight haze
covering it, no shavings), and the bottom of the pan was absolutely free
of debris. The fluid smelled new and clear (zero burn scent). I put on a
new screen and replaced the fluid, adding some lucas as a kicker.
I brought it into several shops and they would only tell me "oh, about
two thousand dollars", but yet I'd hit a bump and I'd have 4 gears back
up shifting and down shifting normally as if I never had a problem (but
the idle problem prevailed).
Each time the transmission would randomly go ignorant, I'd checked the
replaced the TPS and calibrated, the idle issue when away -- and so did
the transmission issue (save one). I did not get overdrive back. It's
been a month, and I am at another dead end on what direction I should take.
I do not know if I damaged the 4th gear/overdrive planetary when I ran
low on fluid (temperature wise) back in May, or if I have a pending
overdrive electronic issue? MT2500 didn't shed any usable clues.
Based upon each of your previous postings with advise, I am going to
break open & look into the wiring harness and also disconnect at the
bulkhead to check the contacts this weekend.
Do you think my neutral safety switch is over due at 270k miles?
--Percentage wise? Aisin Warner 30-40LE.
Any Suggestions?
Thanks,
Ken

Post by Will Honea

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.

The factory manual for the Renix system (same as my '88 Commanche) says that
the reference voltage should be 5.0 volts supplied by the computer but
yours may be running slightly differently. My adjustment procedure (from
the manual) is .86 volts ouput with the throttle at dead idle to 4.95 at
WOT. If it is the 5.0 reference, you'll also find that the MAP sensor
supply is high. If that's the case, good luck finding another
computer! As I recall, the Rennix system was only used in 87 and 88 -
maybe a few of
early the 89's had it butthe 90's on used the MOPAR unit. That had
totally
different sensors and was set up for the HO engine with different intake
manifolds and headers along with a reworked head. If the engine runs OK
beyond the idle/WOT performance, you might be able to repair the voltage
reference inside the computer but that's chancy - I've never gotten the
schematics for that beast.

[Will Honea]

Post by k***@earthlink.net
Since 10/2009, just wanted to follow up and update on the TPS issue.
I was sure my transmission was an electrical issue, and not a mechanical
one. The TPS seemed to be a part of that premise. In the summer 0f 2010,
after driving without overdrive for a year, I pulled into a sleeply
little town in Mississippi (Pascagoula) and a home grown auto repair
shop. Ole boy said his modis scanner said my brake was depresssed. ---
Overdrive solved by replacing a burnt wire under dash near pedals. Just
saved $2,300 for what 10 authorized mechanics wanted to charge.
Well, it's winter time again and my jeep is following it's attitude as
in the past 5 winters. Cold temperature (35 to 45 degrees) it reeves
over 3500 rpms the first time starting it in the morning. I have to shut
off, and restart no less than 4 times before the reeving of the engine
subsides. Any suggestions? EGR? vacuum? relay?
Your input has been and is appreciated,

My wife showed me how to fix that on a 4.0L I6: KEEP YOUR FOOT OFF THE GAS.

More specifically, the old MJ (Renix system) does this race thing on cool
starts ("cold" around here is generally single digits, +-, and with those
the darned thing starts fine). At those intermediate temps, it will race as
you describe under two conditions: If I give it ANY gas while starting and
(oddly enough) if I pull into the drive in 2nd or 3rd then turn the engine
off without letting it idle for a second or two. The second one there acts
like a restart after stalling the engine taking off from a stop and backs
off pretty quick but I can't figure why it "remembers" a stall overnight.

Two things helped the first of the above two: 1. clean the TPS lug really
well and 2. get some contact cleaner into the TPS itself then work it back
and forth to get the corrosion off.

[Old Crow]

Post by Will Honea

Post by k***@earthlink.net
Since 10/2009, just wanted to follow up and update on the TPS issue.
I was sure my transmission was an electrical issue, and not a mechanical
one. The TPS seemed to be a part of that premise. In the summer 0f 2010,
after driving without overdrive for a year, I pulled into a sleeply
little town in Mississippi (Pascagoula) and a home grown auto repair
shop. Ole boy said his modis scanner said my brake was depresssed. ---
Overdrive solved by replacing a burnt wire under dash near pedals. Just
saved $2,300 for what 10 authorized mechanics wanted to charge.
Well, it's winter time again and my jeep is following it's attitude as
in the past 5 winters. Cold temperature (35 to 45 degrees) it reeves
over 3500 rpms the first time starting it in the morning. I have to shut
off, and restart no less than 4 times before the reeving of the engine
subsides. Any suggestions? EGR? vacuum? relay?
Your input has been and is appreciated,

My wife showed me how to fix that on a 4.0L I6: KEEP YOUR FOOT OFF THE GAS.
More specifically, the old MJ (Renix system) does this race thing on cool
starts ("cold" around here is generally single digits, +-, and with those
the darned thing starts fine). At those intermediate temps, it will race as
you describe under two conditions: If I give it ANY gas while starting and
(oddly enough) if I pull into the drive in 2nd or 3rd then turn the engine
off without letting it idle for a second or two. The second one there acts
like a restart after stalling the engine taking off from a stop and backs
off pretty quick but I can't figure why it "remembers" a stall overnight.
Two things helped the first of the above two: 1. clean the TPS lug really
well and 2. get some contact cleaner into the TPS itself then work it back
and forth to get the corrosion off.
--
Will Honea

I think that cleaning the IAC pintel and throttle body might help too.

[k***@gmail.com]

Old Crow, Wow Thanks for even more direction. What is "IAC pintel" as I
haven't come across those words before. Thanks for your input --Ken

Post by Old Crow

Post by k***@earthlink.net
Since 10/2009, just wanted to follow up and update on the TPS issue.
I was sure my transmission was an electrical issue, and not a mechanical
one. The TPS seemed to be a part of that premise. In the summer 0f 2010,
after driving without overdrive for a year, I pulled into a sleeply
little town in Mississippi (Pascagoula) and a home grown auto repair
shop. Ole boy said his modis scanner said my brake was depresssed. ---
Overdrive solved by replacing a burnt wire under dash near pedals. Just
saved $2,300 for what 10 authorized mechanics wanted to charge.
Well, it's winter time again and my jeep is following it's attitude as
in the past 5 winters. Cold temperature (35 to 45 degrees) it reeves
over 3500 rpms the first time starting it in the morning. I have to shut
off, and restart no less than 4 times before the reeving of the engine
subsides. Any suggestions? EGR? vacuum? relay?
Your input has been and is appreciated,

My wife showed me how to fix that on a 4.0L I6: KEEP YOUR FOOT OFF THE
GAS.
More specifically, the old MJ (Renix system) does this race thing on cool
starts ("cold" around here is generally single digits, +-, and with those
the darned thing starts fine). At those intermediate temps, it will
race as
you describe under two conditions: If I give it ANY gas while starting and
(oddly enough) if I pull into the drive in 2nd or 3rd then turn the engine
off without letting it idle for a second or two. The second one there
acts
like a restart after stalling the engine taking off from a stop and backs
off pretty quick but I can't figure why it "remembers" a stall overnight.
Two things helped the first of the above two: 1. clean the TPS lug really
well and 2. get some contact cleaner into the TPS itself then work it back
and forth to get the corrosion off.
--
Will Honea

I think that cleaning the IAC pintel and throttle body might help too.

[DougW]

Post by k***@gmail.com
Old Crow, Wow Thanks for even more direction. What is "IAC pintel" as
I haven't come across those words before. Thanks for your input --Ken

Idle Air Controller.
http://www.revbeergoggles.com/tb/tb.html
doo-dad #2

The pintle is inside. You can see it when you take the plastic motor
and housing off.

Which reminds me. Got to do mine again.... (looks outside).. when it's warm. :)

[k***@gmail.com]

Will, You are so on target with the extreme cold starts. The engine
functions like brand new, no reeving and as smooth as heck. Thanks for
your input. The TPS is under 2 years old, and this reeving has occurred
with it being new (through the years). I might consider the pedal
linkage in the process as I do not touch the gas pedal while starting
out. I wonder if the renix ecu had this issue in 1987-90ish. Would not
they have made a recall on it? I put a new renix in a couple of years
ago. I still have to think there is something can be done for the
contition.

Post by Will Honea

Post by k***@earthlink.net
Since 10/2009, just wanted to follow up and update on the TPS issue.
I was sure my transmission was an electrical issue, and not a mechanical
one. The TPS seemed to be a part of that premise. In the summer 0f 2010,
after driving without overdrive for a year, I pulled into a sleeply
little town in Mississippi (Pascagoula) and a home grown auto repair
shop. Ole boy said his modis scanner said my brake was depresssed. ---
Overdrive solved by replacing a burnt wire under dash near pedals. Just
saved $2,300 for what 10 authorized mechanics wanted to charge.
Well, it's winter time again and my jeep is following it's attitude as
in the past 5 winters. Cold temperature (35 to 45 degrees) it reeves
over 3500 rpms the first time starting it in the morning. I have to shut
off, and restart no less than 4 times before the reeving of the engine
subsides. Any suggestions? EGR? vacuum? relay?
Your input has been and is appreciated,

My wife showed me how to fix that on a 4.0L I6: KEEP YOUR FOOT OFF THE GAS.
More specifically, the old MJ (Renix system) does this race thing on cool
starts ("cold" around here is generally single digits, +-, and with those
the darned thing starts fine). At those intermediate temps, it will race as
you describe under two conditions: If I give it ANY gas while starting and
(oddly enough) if I pull into the drive in 2nd or 3rd then turn the engine
off without letting it idle for a second or two. The second one there acts
like a restart after stalling the engine taking off from a stop and backs
off pretty quick but I can't figure why it "remembers" a stall overnight.
Two things helped the first of the above two: 1. clean the TPS lug really
well and 2. get some contact cleaner into the TPS itself then work it back
and forth to get the corrosion off.

[Will Honea]

Post by k***@gmail.com
Will, You are so on target with the extreme cold starts. The engine
functions like brand new, no reeving and as smooth as heck. Thanks for
your input. The TPS is under 2 years old, and this reeving has occurred
with it being new (through the years). I might consider the pedal
linkage in the process as I do not touch the gas pedal while starting
out. I wonder if the renix ecu had this issue in 1987-90ish. Would not
they have made a recall on it? I put a new renix in a couple of years
ago. I still have to think there is something can be done for the
contition.

Ken, my MJ is an 88 so we're in sync on the year.

The IAC pintle is the little shaft that drives the pointy end inside the
throttle body. To clean, I usually pull the IAC body off and squirt the
whole front end (the part with the spring and the pointed knob on the end)
with carb cleaner or brake cleaner - which ever is closer at the moment.
Word of caution: NEVER turn the key on while that sucker is off the throttle
body or you'll wind up chasing little bitty pieces all over the garage!

While you have IAC motor off, clean the connector pins (WD40 works just fine
- just blow the connector good and dry afterward) and take the opportunity
to clean the inside of the port. A lot of gunk collects inside there and
you really can't clean it with the motor in place. I don't consider the
problem worthy of a recall since cleaning the throttle body et. al. is a
regular maintenance step anyway. The IAC stickiness gets worse with age as
more oil is drawn back thru the throttle body from the crankcase purge - as
seen by filthy, oily air filters.

[bllsht]

The ECU supplies both voltage and ground to the sensors.

There are two splices in the sensor ground circuit that have been very
troublesome on the early (87 and early 88) 4.0L XJ/MJ. They used a
bulkhead connector on the firewall that connected the engine harness
to the injector harness. The splices are within about a foot of that
connector, one on each side. They are crimped and duct taped inside
the harness.

In the engine harness, there is a 3 into 1 splice. The single wire
goes through the bulkhead connector, then a 1 into 3 splice in the
injector harness. The circuit is brown with white tracer.

You can manipulate the harnesses in the area of the splices and watch
the TPS voltage go nuts with a scan tool. I've never seen a physical
problem with the splices (no broken wires, corrosion or high
resistance), so it appears to be the way they routed the wires in the
harness. Maybe too close to, or not protected well enough, from other
current carrying wires. Whatever it is, you can open the harnesses
and pull the splices out, isolating them from the harness and the
problem goes away.

Since the bulkhead connector can be problematic also, I'd suggest
bypassing it altogether. Just solder the 3 wires in the engine
harness to the 3 in the injector harness. The splices are close enough
to each other that it's easy to do. Tape it up and it looks good and
no more problems.

Post by k***@earthlink.net
1987 JEEP CHEROKEE CHIEF, 4Door,4WD, 6 cyl 4.0L Automatic
VIN# xJCMRxxxxHTxxxxxx with a RENIX ECU.
Where does the Throttle Position Sensor input voltage come from?
I replaced the TPS 2 years ago and calibrated the OUT divided by the IN
@ 83%, and it worked well until recently.
My current TPS readings are IN = 7.81 vdc, and OUT = 5.65 vdc.
I am suspecting my problems are centered in the origin of the voltage
being supplied too high to the TPS and not the TPS itself.
Any advice is welcomed, thanks.