Hello, I just picked up a 97 A4. The po swapped the DDT out for a EZS transmission. He said that the TCM needed to be reprogrammed. My question is are these 2 transmissions compatible?

It's not that the transmissions have to be compatible, it's the TCU/TCM that controls them. Being that they probably use the same physical TCU, the programming on them is different for each model of transmission. The program for the EZS transmission needs to be uploaded to the TCU in order to control it correctly. However, if it performs without any issues and doesn't trip the Check Engine Light, you might be able to get away with not having to pay the "stealer" to re-program the TCU.

Thank you. I was told by an Audi transmission mechanic that there is no such thing as a tcm reflash. I think he just wants me to sell him my car for a cheap price. The car doesn't go in any gear. The guy that sold it to me said it needed to be reprogrammed.

I can't swear to the fact that they can or cannot be reprogrammed but it got programmed somehow and therefore can be programmed again. It may be as simple as swapping out an EPROM chip. Heck I don't know. OR.. If you can find a TCM for EZS transmission and swap it out.

Just did a bit of searching and found one on Ebay. http://www.ebay.com/itm/AUDI-VOLKSWAGEN-PASSAT-A4-TRANSMISSION-MODULE-EZS-TCM-TCU-8D0-927-156-DE-/231675464453?hash=item35f0ef0b05&vxp=mtr
It think it'd be much easier and cheaper to just swap the TCM.