Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
This problem can be a faulty ignition switch,cutting the power to one of the ignition powered circuits that operate engine controls.
It can be an ignition system failure,in the module or computer.This is sometimes a communication error that causes this or a faulty input sensor.
I would suggest driving to duplicate this problem with a passenger that is viewing computer data with a scan tool .This is very helpful when trying to track down an intermitten problem.Check for failure codes that may help also.