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I'd be double checking everything I unplugged etc.
Codes may not help because if somethings not plugged in or a plug is completely unplugged there'll be a heap of codes. Might give you a clue though (eg, IAC error might be there, indicating the engine loom is not plugged in).
Can you use the old paper clip diagnosis method? That should give you codes.
that will do it every time.Yeah big white plug