If you didn't get the rash of 16 y/o's on vortex then there is great wisdom there. I hang out on a local VW board and I don't hear of 2.slow MAF's failing (VR6 - yes, 2.0 - no) - the 2.0 is usually pretty bulletproof (even if attached to a lousy quality car =)

There is an OBD-II code for "cylinder misfire" that will light the CEL - this will only confirm what you already know - it starts missing on one cyl. and runs rougher and rougher. Hpoefully there are other codes locked in.

When this happened to my then-girlfriend's Neon- (and her friend's civic...) new plug wires did the trick.

Changing characteristics as the engine gets warmer does point to a bad coolant temp sensor (as already mentioned) but I've never heard of one of those causing a cyl to stop firing. As I remember my brother's Bentley (he has a VR6...) it said something like "If the ECT doesnt see a correct Engine coolant temp then it will set mixture as if the coolant temp was 210*F..." - that was the VR6 motor though (be only slightly glad that you don't have a VR6...)

-John

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2009 Kia Sedona
2009 Honda Odyssey EX-L
12006 Jetta Pumpe Duse
(insert Mercedes here)

Husband, Father, sometimes friend =)