I have a 2002 chevy z71. It just recently started having the following issue once every couple months. When I attempt to crank it, it will not even attempt to turn over. If I manipulate the gear shift up and down through the gears and back to park, It will eventually crank. No mechanic has been able to diagnose the problem because of course it cranks fine when at the shop. Any ideas?

 

This is just a guess, but from your explanation it sounds like the neutral safety switch is flaky. Will it start in neutral?

 

what he said

 

No. When it is acting up it will not start in park or neutral.