2002 GMC Sierra Starting Issues

My 2002 extended cab truck is having an annoying, intermitant, un-reproducable starting problem. Sometimes I will turn the key and it will not crank…no starter, no nothing. The dash lights, etc all indicate it is starting. If I hold the key to the start position long enough, it eventully cranks and starts right up (so far).

The dealship mechanic is stumped. It even did the same thing in his shop. Starter and battery test OK. Have changed the security transponder, the ignition switch, swapped the ignition and starter relays.

Any suggestions???

No ideas at all??

Not no ideas, but close to it. Grounds. Somewhere; either on the engine or transmission is a ground wire that connects the eng/trans to the body or frame. It could be broken or the body end may be rusted. Other things include the starter solenoid, dirty battery terminals or battery cable ends.

I’m not sure on this truck, but a lot of vehicles have a switch on the gear shift to prevent the car from starting when it’s not in park or neutral. Could it be that you bump the gear shift while holding the key?

Sounds like some connection is causing a voltage drop. When the problem occours make a effort to see what voltages are present along the starting circuit,at the switch,at the relay,at the starter.This data will help in narrowing this down.Are they charging you shop labor rate,by the hour,however long it takes? if yes you may find a guy who will put a limit on the bill.

I have tried wiggling the gear shift and holding in place. The battery terminals and cables are clean and tight. The problem is that when it was in the shop for routine service, everytime it has starting issues, by the time they got the tech to the truck, it started.
At this point, I am being charged shop rates but have made a case for major discounts next time it goes in.