I am not vast in the knowledge of the audis but had driven a 2.3, recently I got a supposedly 1992 2.8 AAH A80, only to discover later when the rpm starting falling below 800 that engine swap to 2.6 ABC had been done on it. In this part of the world, audi knowledge is quit at low so getting help is very limited. I have done the MIL thing on the Hitachi MMS200 ecu and can blink out the code. these are 4431 and 1111. I discovered a 2 wire unplugged connector meant for the Idle valve hanging redundant, while the throttle Head has a 4 pin stepper idle valve. I understand the ABC engine makes us of the MAP and I can see the see the 2 pin connector for that. my are questions are (1) Can ABC engine work correctly on the MMS200 ecu system. (2) with the blink code 1111 must I change the ecu (3) what should I do to relief the low rpm.