I just had 3.42s installed on in my 2000 A4 on Monday. The installer used LS1 Edit to reprogram the current Diablo program for the 3.42s. He also said he would firm up the shifts, even though I allready added 5% line pressure. Now after about 15 minutes of driving the low speed shifting gets very firm and feels as if it's slamming into 2nd and third gear. The car shifts perfect until the trans temp gets to about 150-160 then it shifts like a kick in the rear. All shifts @ WOT are nice and firm, just the low speed problems.

Any ideas, could something have gotten un hooked, could it be a programming problem, could it be low on fluid, could it need a trans rebuild ? What kind of signs do the A4 transmissions give when the need repair ?

 

I had the same problem when I changed to the 3.42 with my A-4. I have the predator as well. The problem you have is the same as mine had. while the LS1 edit should have corrected it you should do what I did and have predator do a custom program so that all is compatible.. I am in Montclair 2 hours south of you and I have the program to upload to the computer to send it to Diablo. Call me tomorrow at (800)979-4866 Mark VNM Performance.

 

Thanks Mark, I really appreciate your help. I would have stressed all night tonight and all day tommorow worring that I needed a new transmission.

 

you may be seeing the P1870 error code as well with the tranny shifting like that.

I don't know if combining the Predator and LS1Edit was a good idea. There's more to the reprog than just shift points. The TCC Slip Table needs altered as well, or the PCM will be faked into believing there is too much tranny/TC slip and command extremely high line pressures to compensate (when there was no "real" slippage to begin with).

Why wasn't the Predator used exclusively

 

I smell a P1870 code!! Check your DIC!!!

 

What is the description of code P1870 ?

 

This is what I had Greg. The custom Program from Diablo has given me a sweet ride.

 

it's a slip code error. In a nutshell, there is a table in the PCM that supposed to detect a slipping tranny/TC. It does this by comparing the RPM to MPH while in 4th when the TC is locked. (Though I have read that it happens in 3rd or 4th).

When you change rear axle ratios, you get more RPM at a given MPH than before.
If the new RPM is above the threshold set in the TCC slip table, then the PCM commands the tranny to increase line pressure to compensate... falsely thinking there is a transmission/TC problem. Of course there is no improvement, since there is really no increased "slippage".
Seeing no improvement, the PCM commands even higher line pressure. You eventually get neck-snapping shifts, and the PCM will eventually set the P1870 error code... and possibly the CE light.

So the error thresholds of the TCC slip table need to be updated to allow the increased RPM to be considered normal - due to your more radical rear axle ratio upgrade.

LS1Edit can do the job, if the operator knows what they are doing. The newer Predators can do the job... right out of the box. The older Predators will need a custom tune file generated.

 

It sure sounds like a P1870.

Now this one I am unsure on. I always thought that you had to flash back to stock using the Predator if you wanted to change over to LS1 edit or HP Tuners, etc. for your PCM programming.