I'm looking for a stock ecu for my 2000 audi S4.
It has a 2.7 twin turbo 6 speed standard transmission.
The numbers on my old ecu are
4B0 907 551 k
0 261 206 561
I was told that as long as it came from a 2000 - 2001 audi with a 2.7 twin turbo, it did not matter if the numbers matched.

Does anybody know if this is true?
I would hate to buy one and have it not work.

Thanks

 

It does matter. The safest bet is to use the same part number as what is in your S4. Having said that IIRC Audiworld had a short list of ECU part numbers that could be interchanged.

Some ECU's were interchangeable during the platform production run and most are not. For example you can't use a stock ECU from an Automatic Transmission S4 on a Manual Transmission S4. You should not use a stock ECU that came from a 2.7T with SAI on a 2.7T that does not have SAI hardware as it will always produce a CEL, etc. Aftermarket reprogramming may be an option to get around this but it is recommended to verify interchangeable ECU part numbers with the software vendor before purchasing your next ECU.