OK folks. 1996 A6 Quattro V6 4spd auto here; babied since birth. 150M miles; 95% hiway and always old person driven.

So I went to the most respected local Audi indy when my A6 died on the hiway and it was not going anywhere. They diagnosed a faulty CPS (camshaft). $1100 later, it runs and I am temporarily happy.

Get the car back home and the speedo is bouncing all over. OBDII says it is the VSS so I replace that. Good to go for a few miles.....

Then the tranny starts shifting hardcore; like getting freaking rear ended in upshifts AND downshifts. WTF??? Indy said it was like that when they got it.
(note - they had the car for a few weeks and the battery went dead dead dead for some unknown reason; probably enuf for the ECM to loose its memory is my guess???)

New tranny fluid and filter do NOTHING to smooth out the rough shifting That was fun too!!! (A Schwaben Multi-Function kit 007311SCH01A is THE BEST SOLUTION to that fluid change hurdle.) https://www.ecstuning.com/b-schwaben.../007311sch01a/. And this helps for that too: http://www.blauparts.com/audi/audi_f...on_fluid.shtml http://www.blauparts.com/proddetail.asp?prod=F2A1003-01 http://www.blauparts.com/proddetail.asp?prod=J1D2107-B

So my instincts (and some OBDII confirmations) tell me to replace the ECM and TCM. Done. Matched the numbers exactly as you should. Only like $200 for these off of EBAY (2 ECM's and 1 TCM; just in case).

But even after all that swapping out, the babied car/tranny was literally still KICKING my *** on all shifts.

I hesitated to buy the RossTech VagCom dongle after a company rep I spoke with "doubted" it would be of much use to me after I described my TRANNY problems on my 1996 A6 Quattro. He said the Hitachi ECM's for that model were touchy.

But I took the $200 plunge because VCDS VAG-COM looked like it was lightyears ahead of OBDII and much more versatile. It would allow you to "PROGRAM" things, not just read them. I was sold.

So I run the initial VagCom autoscan and the Engine 01 module shows a repeating DTC VagCom, not MIL(?), fault; 18020 = "ECM incorrect coding".

That takes me to the VagCom Engine "coding" module. The software coding field had a sweet popup menu detailing the five digit XXXXX ECM software code.

BINGO. For this ECM and setup, the ECM's always defaulted/reset to 01001 software code which is an A4, FWD, 5 speed manual. WHAT THE HELL??????

But I have an AWD, 4sp auto, ZF 01F H18, A6. So I re-coded to "01242" per the popup menu and hit "Do It". Plug that in; recheck autoscan; and there are no DTC's in the ECM. Sweet. Lets move on.....

ROADTEST RESULTS: runs like it is off the freaking factory floor; 21 years later. NO BUCKING OR TRANNY ISSUES after three hours of city + hiway driving!!! I CANNOT EVEN FEEL THE CAR SHIFT - ALMOST HAVE TO WATCH THE RPM's!!!

All I can say is that the RossTech program has paid for itself many times over after this nightmare of mine; I was on the verge of throwing in the towel and dumping my treasured baby of 21 years. And all she needed was the proper ECM software code entered.

Hmmmm. Wonder why the indy didn't check for that or tell me??? C'mon, $1,100 and you can't run a 2 minute VagCom check???

Something is to be said for DIY'ers guys and gals!!!!!! My 21 year old lives on and on and on.................

Email me with questions or comments: dchoran1@gmail.com

Hope this helps somebody else someday.

THANKS!!! Dave H. Appleton, WI Sept 12, 2017

 

Thanks for the comments! I switched from a bluetooth ELM327 OBDII connector and Torque on the phone (cheap and useful for less than $20 and displays many fault codes) to a RossTech connector and software a couple months back. Night and day difference in capabilities.

I hope to keep my 2001 TT Quattro running as long as I do!

Russ