My A4 shifts great and was just recently rebuilt. However I have had this problem from the beginning and it still persists. When I drive long distances ... (about an hour i guess) ... it starts to shift real hard even at about 1/4 throttle. If I let the car sit for a while and turn of the engine, it wont do it again for about 10 - 15 minutes. Has anyone else had this problem?

 

has anyone ever heard of this happening????
maybe I just have a freak transmission.....

 

I'll move this over to the Drivetrain forum for ya...

 

I do not know if i can be much help but maybe someone will see this thread and respond.

I just bought my 1995 Z28 Convertible with the A4. It has 3.73 gears and this has been a real learning experience. Lately my transmission has been shifting completely weird. At low throttle inputs it shifts fine with no problems. If I go further than 40% it would hang the shift or drag it out. At wide open throttle it would shift way up there and 2nd to 3rd would not shift out unless I lifted.

Well, I thought I had checked the tranny fluid... I looked at it while idling in park and saw that it appeared to be full. I was wrong. It was two full quarts low. So, I top it off to the hash mark and then drive 25 hwy miles in the rain. As the weather finally cleared on my commute I left a stoplight and to my surprize this car RIPPED second gear!! Hell yeah!! I am happy but also concerned. I was in "D" not Overdrive. Is this the way this car should shift when in D. I mean its leaving a good 3foot scratch at half throttle in "D" when I accelerate.

I am wondering if this tranny is about to "Go" and now its giving me its best before it dies. I have no slippage or any indication of such. So, should I be worried? I am now wondering if this car has had a shift kit put in it. It shifts completely different when in Overdrive detent.

Any help?

Thoughts?

Laughter?

 

Sounds like an EPC (Electronic Pressure Control) solenoid problem. If I had it in front of me, the first thing I'd do is scan it, and check the data parameters. The Scanner will give you EPC PSI, and volts. It may be losing EPC voltage, which will cause the transmission to default to max line pressure. Something EXTERNAL of the transmission can cause this. I'd also put a pressure guage on it to see what line pressure is when it starts acting up.
I'd say you have an EPC problem...Rather it be voltage, or the solenoid itself.

Let me know what fixes it.

Frank
All-Trans Transmissions

 

Wayne. Do you have any codes/SES light. You probably have the P1870 code. It is only on OBD2 cars. It causes the PCM to apply maximum line pressure which causes a harsh 1-2 shift. When you shut off the car it resets. Can only happen when the tranny reaches full temperature. Do a search on it. There is some info out there on it.

 

Frank,
Thanks for the help .. If I cant figure it out in the near future maybe you can have it in front of you .. I'm only about an hour from Elkton and drive down rt 1 all the time.

Vegas,
Your idea sounds like a good one too. I'll check my codes and see what comes up. If it pops up where do I go from there?

 

A tranny cooler reduces the accurance of the P1870 code. So if you dont already have one, I would start there.

 

Code 1870 has nothing to do with heat. It's mostly caused by fluid leaking past a bad bore in the TCC control valve, in the valvebody.

Frank