I've searched all over the fourms and couldn't find the answer to my question. I just bough a 2001 Audi A4 1.8t Quattro. It only came with one key and didn't come with the bottom half *3 or 2 button key fob.* I have a new remote my friend gave me the FCC ID number is MYT8Z0837231 and it also says 4D0 837 231 P. Is this remote compatable with my car? If so i was told by a audi tech that the car needs to be reprogrammed for the remote and the reprogramming instructions found on this forum wouldn't work. Is this true?

you can't reprogram the car to the key... the key can only be programmed to the access start / immobilizer / central locking control modules.

that number needs to match the number that originally came w/ the lost remote. call your audi parts department and they can provide that number. if it does, then it can be programmed