Originally posted by Rocky
I don't understand your question about a misfire and diagnostic test.

Even if the car is not misfiring, a bad wiring harness can cause a misfire code to trip or any code as a matter of fact.

Put it this way, if the MAS was perfectly good, you could get a bad reading because of the wires.

Check the wires too see if the insulation has gone bad...and not just the MAS, the wires that go into the coils and stuff. The engine harness connects EVERYTHING not just the MAS.

A misfire can happen in quite a few places. Can be bad coil, coil ends etc.
I think he's saying that no missfire codes showed up in the diagnostic test, although I'm not quite sure what else could make the engine sputter, probably several things that a newbie like me doesn't know about