Hey there I've had this problem for quiet some time now and am seeking desperate rb guru knowledge,so my series 2 rb25det auto r33 is reading error code 21 thru the diagnostic port , iknow its ignition signal code ,I've replaced coils ,sparkys (twice),CAS,AFM,and still the car didn't start? Now funny thing igot ahold of a rb25de auto ecu and loom wired it up too see if it will start and it DID on 25de brains(ecu)? yet no go on my 25det auto ecu ? Does this mean the ecu needs resetting or perhaps fried ? This problem just ocured out of the random after turning car off 1 day ?!?!? All help apreciated