E.A.T. Problem with my 540ia??? (long)

[ScottM]

I switched over to the EAT chip as one of the first test cars for them about two years ago. I have a 1995 540ia with 74K miles on it. About a year ago I noticed a problem with the shifting of the tranny. At 45mph or higher, if I pushed the down the throttle, the tranny began to downshift with a thump. This was very intermittent but now it does it all the time (like it learned to do this???).

Took the car a great local indy shop where they said the tranny chip had an updated chip available. They tried 4 different but new chips over 2 days but the tranny failed to even work without the original tranny chip back in it. They did not understand why. I then pulled the EAT chip out and went back to the original chip to see if it would make a difference...well the cold chill of the TRANS PROG error message was all I got. I put the EAT chip back in and it is back to its thumping problem but at least it runs.

Any ideas out there??

ScottM

[ra_pro]

What I found with EAT chip and tranny is that if the engine is not running in its optimal range the shifting is a bit late and hard. Once the engine is fine, with no 'check engine' on, the shifting is fine.

When I got my tranny checked it turned out it was missing 3 liters (quarts) of fluid. The tranny occasionally displayed 'trans prog' message but shifted OK. Did you have tranny service done? Do that it might help.