Hi, i see a long time gone, but how you solve this problem, do you successfully cross-flashing 8D0907551 M-box file to 4Z7907551M? Because I'm thinking to do that on my 2002 Audi A6 6-speed 4B0907551AK but I'm afraid to brick the ecu. Thanks
"I bought used 4B0907551K ecu for tuning"
For you a6 K-box. Searched quickly so that errors are possible, check. Do not forget to recalculate the checksum. I attach ols file 4B0907551K.ols