456 Check Engine Light - Which ECU to check?

Sorry can't answer your technical question, but surely the best course of action would be to take it back to where every you've just bought it from and make sure they put it right - as you said it was supposed to have an inspection done on it.

Hope you get it sorted.

 

Why do you think the ECU is the problem? Generally, the Check Engine light is telling you that the ECU *detected* a problem, not that the ECU itself is broken. You need to go to someone who can read the codes and tell you why the car thinks there is a problem.

If it's a 95, you probably need to go to a dealer. If it's a 97 or a 456M, most independents should be able to take care of you also.

 

Same thing on mine today "Check Enige 1-6" went on and off a few times over a one hour period cruising on the highway. Car ran great, I don't get it?

 

If you think that 1-6 is dead, why not check the relay first? That's cheap to replace.

relays do go bad often on our cars, so I would check it first.

 

pray its not the valve guides.. check the posts about valve guides.. find out if the car was smoking too much at startup and oil consumption.

 

Alberto, if you had all 6 cylinders of one bank dead, your car would hardly move.
You may have one or maximum two cylinders misfiring or not firing and still move, albeit at a slower pace, but not all 6 of them.
Anyway, when there is a problem, the rule of thumb is to start always from the most obvious and easiest to occurr (and catch), not from the most difficult and expensive (like the ECU).
In your case it may be something that was done or disconnected during the inspection.
Check the plugs, make sure all the caps are ok and secured on the plugs, that all the wires are secured.
Check that all the electrical connections on the one side are secured in place.
Make sure there is no air flow restriction to that side, such as leaves in the intake or the air filter dirty.
If you cannot find anything, then go somewhere where they can read the code.
Good luck,
A.

 

IMHO, I'd take the car by a dealer or independent mechanic and just get the codes scanned. The 456 is an intensely complex vehicle and there are many many electrical points capable of throwing a CEL. The $250-ish getting a good scan will save countless dollars that might otherwise just be tossing components into the car thinking it 'might' be the problem.

But then again, randomly throwing parts into the car might help a lowly internet merchant like myself

Just my 2-cents.