my son has an R32 GTST with some mods- recently it has had an intermittent misfire- will drop to 5 cylinders , then after a minute or two , come back to 6. Now- more recently- last few days stays on 5 and has even dropped to 4.
Have checked and changed coil packs- all good
changed plugs
listened to injectors- all firing
Problem SEEMS to be # 2 cylinder
changed over ECU last night with one from a friend - ran on 6 cylinders at idle, but ROUGH and missing under load.
The wiring seems pretty worn and tired, but really struggling to track this problem down- any help -GREATLY appreciated!