Alright so I recently bought a 2000 prelude. I coma me to find out it had been swapped from an a4 to an a1.it has been throwing the cel for the iacv. It has been running very rich and seems to have the timing retarded a bit. The car is still obd2 from what I can tell. I don't see any obd1 plugs or anything. Anybody have this problem? Or what should I do? Also when you change ecu what does it mean if it's chipped and also how do you tune with chrome.