An engine with a bad MAF sensor may be hard to start or stall after starting. It may hesitate under load, surge, idle rough or run excessively rich or lean. The engine may also hiccup when the throttle suddenly changes position. A maf problem should but not always set a code. Right now mine is hunting for idle and will eventually stall after a few surges. Mine has readings in hptuners. I unplug the maf and it's a lot better but not 100%. I have one on order and will be here on Tuesday so I will know for sure then. From what I've read, theses 3800's commonly have a maf failure problem. Here's how to test.
Part 1 -MAF Sensor Test (P0101, P0102, P0103): GM 3.8L (1996-2005).
