im having a problem with a 2002 B6 A4 1.8T and i think its the ECU. what happens is it misfires on cylinder 4 and there is no fuel. also when i first start the car the radiator fan comes on high. i was wondering if i could take a VW 1.8T ECU and use it in place of this cars ECU just as a test to rule it out. the cars ECU part number is 8E0909518BC.
You can use that ecu in it's entirety, but you must use 518AF, AK, or BC files on it. I'd go AF as it is the closest to your car.