VERY hard to diagnose problem:fuel injector cleaner my check light appears---> (read)

[xjeeper]

About 2 months ago i put in a bottle of Lucas fuel injector cleaner @ 94,000 miles in my M. Ever since then at part throttle acceleration sometimes around 3-4,000 rpm and everywhere in-between the check engine light comes on and i can feel the car slow down....i mean it like really cuts the power to the engine until is hits around 4500 rpm when the light goes off and the power returns. It is driving me nuts and I have no idea where to start, any suggestions?

[Lopaka]

1. What year ///M?
2. Have you tried the fault code test? real quick, here is how to do it... turn ignition to on position but do not start. press the gas pedel 5 times within 5 seconds. You will see the check engine come on, then off, then on again. Now read the codes (4 numbers all together separated by a 1 second pause).

Off hand, (I'm guessing here) it sounds like a fuel/air problem. and possibly a knock sensor, because the computer will retard the timing so as not to hurt the engine. The cleaner probably had nothing to do with the problem, but sometimes those cleaners can hurt the injectors. (again, this is just a "WAG" (wild ass guess)).

Do the fault code test first.