So I'm pretty sure I need a new Transmission Control Module (TCM) for my B5 A4 (97 1.8 Turbo, no Quattro).

I found a guy on craigslist selling a TCM for $50 out of a car that hes parting out. Its a 98 A4 2.8 Quattro. The part number on the one that he has is exactly the same except for the very last letter. I've been told that the last letter just represents the different "versions" that came out at different times.

I've also read on here and other forums that the B5 1.8 Turbo and 2.8 Quattro use interchangeable Transmissions.

So if I buy this TCM will it work in my 1.8 Turbo Non-Quattro?!?

 

To my knowledge, the only difference between the auto tranny's on the 1.8 and the 2.8 is the ratios, but I also don't know exactly what the TCM does. I would think there would be some kind of problem switching TCMs between the two. I'm sure one of the Audi Tech's will chime in here and make me sound dumb (lol) but based on my limited knowledge I would say no.

 

Its really not safe to assume it will work. Most of the VAG part number id's what car/platform/engine its for and what function does. That last few digits/places are the most important. That last letter could be big deal, or not. I would assume it won't work until you can find someone that can tell you what the difference is between the versions.

 

Damn! Ok, so does anyone know the car I would have to get one outof?

I refuse to spend $2000 with the Stealership to get one from Germany, when there are lots of cars around here being parted out.

Can I just pull one from another B5 1.8 Turbo with no Quattro?

 

Hopefully someone with inside info will respond.

If there is an aftermarket part, you can sometimes look at vendor descriptions to see if they say different part numbers are compatible. But this sounds like a VAG sourced only part.

In the mean time, I'd be searching google and forums for mentions of the part description and both part numbers.

Maybe the one you found will work, but you can't count on the fact that it is just one letter off as indication.