In Reply to: M3 Check Engine light posted by bri on May 25, 2001 at 10:49:17:
the check engine light seems to come on due to the fact that there are many sensors and devices situated around the engine. One or more of the sensors is failing/intermittant failure. The easiest way to find the fault is to attach a code reader to the engine which will test for any stored faults, indicating where the fault is, it will also drive the actuating motors, ie the injectors, coils, fuel pump, etc, to check for functioning, lastly it allows you to monitor an engines characteristics while running. Expensive kit so a dealer or good garage will test, test charges can be expensive, but will erase prob, before the engine dies on you. Hope this helps.