Engine/Transmission (1998.5 - 2002) Trans problem, TC locking and unlocking????

[Jim Ross]

In my '01, I am experiencing what I "think" is the torque converter unlocking and relocking at various speeds.

It is an instantaneous thing and when it happens, the tach jumps about 50RPM and instantly drops back to where it was.

It doesn't matter if the OD is turned off or not. Sometimes it happens 5-10 times in a row and sometimes it won't happen for a couple of hours or more. When this first started, it only happened when pulling a 27 ft 5th wheel, now it does it even when not pulling anything.

The transmission shop says they are virtually positive that it is not a trans problem or a solenoid problem and they think that it is an "electric" problem, maybe the TPS, or maybe something else.

Anyone have any experience like this?

About 3 years ago, I had a problem with the OD shifting up and down and I wrapped the brown wire on the back of the alternator with aluminum foil and it stopped the problem. Is this current problem something related?

I'm traveling and currently in Lafayette, Indiana and I need to get back on the road to Idaho. I think I can drive it carefully and be OK, but not positive about this.

Thanks for any help offered!!

 

[rjrkihap]

Sounds like the old alternator noise interference problem. Basically, the alternator is throwing off electrical interference that is confusing the signal sent along the orange w/dark blue tracer wire from the APPS the the computer (PCM) and causing the computer to lock and unlock the torque converter.



It's been around for many years and many of us have dealt with the issue. First, clean the battery terminals. Second, re wrap your alternator wire (just to make sure). If that doesn't fix the issue, you can A. Check and clean all your grounds and/or B. follow the DTT or Suncoast fix (should be under FAQ's or search DTT Electric Noise fix).



Ron

 

[JJPage]

Something else to check is the electrical gear selector sensor connection at the transmission, drivers side. It is the round plug, just behind and below the front band adjustment stud/nut.



My front band adjustment was leaking fluid onto that connection, in fact it was saturated causing it to short between the pins. Chrysler recommends replacing the sensor(also repair the leak), I was able to clean mine out with electrical cleaner(canned air), put some dielectric grease on the connection and re-assembled, it worked.



As I said, just something to check.

 

[Ramtuf1]

Over the years, I have made every recommended fix to solve this problem of the TC lock/unlock. From foil to filters to all the recommended wiring changes, I have made them all. Then after a long time with no issues, it started again.



To make a long story short, I also started to see a difference in the charging gauge indication. Eventually it started discharging and I replaced the alternator as the previous one had a lifetime warranty. The charging problem stayed and the problem turned out to be a burnt connection in the small weather tight connector which plugs into the alternator. Replaced the connector and problem solved.



My point is that before I saw the alternator problem, the TC issue started me pulling my hair out and I don't have that much. The arcing inside the connector started reprogramming the TC again. Once the connector was repaired, the TC issue is gone.

 

[Jim Ross]

Thanks to all 3 of you guys.
The transmission shop could not pinpoint the problem, but just like you guys, they think it is the elec noise thing. They unplugged and replugged several wires and then could not get the problem to repeat itself, so maybe it was oxidation on a wire connector?
When I got it back, I cleaned all 4 battery posts; the negative cable on the driver's side battery was not real snug, so maybe that was part of the problem.
The transmission shop told me that my TPS entire unit has "a lot of wear on it", so I guess I need to start saving my money for a new one; $3-400?

 

[ALepley]

Re-run the ground for the apps and wrap foil over the ground to the alternator and clean all grounds on the truck. This will solve your problems. go to suncoastconverters.com and they have instructions on the rewire for the ground.

 

[Jim Ross]

THANKS!!!!!
Right now it is working, but when I get home, I'll follow your advice.

 

[Wooter]

Trans O/Drive In and Out

Had the same problem - Was pulling 5th wheel trailer and it would unlock and lock right back up - Had to have Dealer Re-Flash the computer - They wanted me to "Pay For It" ($225) so, I went to Dlr mgr, and made enough noise, (told him that they were fixing a build in deffect), he told me to forget it!!

 

[Jim Ross]

Drove it over 2K miles back to Idaho and it never acted up one time!
However, since we have an '01 and an '07, we don't need to 2 of these "oil burners", we are thinking we will sell the '01.