Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
It's very rare to see an intermittently bad MAF - they usually just go bad and, when they do, they trigger a code and turn on the check engine light. Also, when the onboard computer (PCM) detects a bad MAF, it will use substitute signals from the crank and throttle position sensors to make the engine run; all of which makes me doubt the MAF as being the cause of the no-start.
Let's try this; go ahead and disconnect the MAF, then try to start the engine. Does it start?
OK. So that tells us the MAF is not the direct cause of the no-start - my advice regarding the MAF would be to erase the code, clean the sensor with the appropriate cleaner and hold off on replacing it for now.
Back to the intermittent no-start; if the engine cranks but won't start, this type of issue is usually caused by the anti-theft system (Passlock VTD) - most likely the sensor in the steering column, with the ignition lock cylinder running as a close second. Diagnosis of the Passlock VTD requires a Tech-II or equivalent scan tool that most licensed locksmiths have access to - they are also much cheaper than the dealer.
Well, not really. You see, if either the key or the switch were the cause, then the issue would happen constantly not intermittently. I'm more inclined to believe the fault lies within the Passlock sensor. Then again, to be sure, the system would have to be diagnosed with a Tech-II or equivalent scan tool.
In the mean time, you can try the auto learn procedure - see attached - and see if that takes care of it.