Engine/Transmission (1998.5 - 2002) Torque Converter Cycling In and Out Again

[CAfricano]

I have had serious "electrical spike" problems causing the Torque Converter to cycle in and out. I have tried all the fixes. All were a temporary fix. I have added several grounds, cleaned the existing grounds, adjusted the APS, replaced the APS, added a DTS noise filter, continuously reset the APS. All this temporarily fixes the problem, but it always comes back.



It has now gotten to the point where anytime I roll the window up or down, or listen to the stereo at a louder than normal volume (non-stock w/amps), the torque converter cycles in and out like crazy. It even seems to cycle to the beat of the music. I assume the cycling happens when there is a demand for electrical power to an accessory. It seems like insufficient grounding, but I don't see how with all the grounds I have added. I can disconnect the batteries for an hour plus, reset the APS, and it is usually alright for a day or two. The new APS fixed the problem for several months, but the problem slowly came back.



I have just replaced my first transmission and torque converter after 279,900 miles (amazing), and I don't want to risk damaging either with this annoying problem. Any ideas? Thanks in advance.



2001, Auto, QC, 4x4, Fass, Westach, BHAF, Bullydog TD

 

[rotohead]

Have you tried this fix from ATS?

https://www.atsdiesel.com/PDF/120505/4th hunt 46 47 RE.pdf

Chuck

 

[raychem]

My sugeestion would be to hook up a scanner and see what the computer (pcm) is doing. The scanner will see the lock-up signal being sent. If the signal is sent for lock-up and it is always there. . you may have another problem... could be lock-up solenoid or something else since you have taken care of the most common problems.



Richard

 

[Tom W]

Have you tried nrw batteries? Optima red top works for me.

 

[CAfricano]

I cleaned the terminals again. Cleaned all connections at PCM with electrical cleaner. Removed APS and cleaned with electrical cleaner. Put back together and hooked up the batteries. So far so good.

 

[bwm471]

it sounds funny but I had this problem and tried many of the things you have. Didn't figure it out untill I drove behind my own truck and noticed the brake lights flickering. a two second adjustment too the switch and fine ever since.

 

[Lsfarm]

List of items to look at [some you have already done]



Clean all grounds [for consistant voltage to the PCM]

Clean battery terminals [for consistant voltage to the PCM]

Install a 'noise filter', [for consistant voltage to the PCM]



See the pattern here? Computers HATE irregular fluctuation voltage.

Old batteries on their last legs will cause irregular voltage output from the alternator.



A bad diode in the alternator will have the alternator's output to have both DC current as well as AC current. The AC current will cause all kinds of issues with the PCM.



You can even try disconnecting the alternator, and driving the truck on batteries only and see if the lockup problem goes away.



i hope one of the above will help. LsFarm.



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