Had similar problem with my GM 6.0 v8 starter staying engaged longer than normal and when truck did start, it ran very erratic for a bit.
Only did this when it sat for a few hours
Chevy Dealership had it 4 days. Reviewed all tech update, etc.
They checked: starter & solenoid, injectors, fuel pump, ECM = still scratching there head!! Finally one tech checked the AMPS at Smart Start = LOW AMPS
They put a NEW battery on the truck, starts and runs like new again!!!!
Guys, check out the battery as wells. Check starting AMPS
I am 69 and worked on all my hot cars for years, never would have thought a weak battery could jack with the electronics this way.
The old battery would crank the truck with out dragging or giving any indication of a weak battery. COMPUTERS!
