Quote Originally Posted by Scottydoggs View Post
thats just what a bad crank sensor does, stalls out driving randomly, it might fire right back up or it might fire up 30 minutes later, or once its real bad stalls and dont fire back up, you could try every morning for a week, then on day 7 it just fires up.

and the best part....it hardly ever sets a code for it. but we all know what it is here.
OK. Intermittent problems are difficult by their nature, so methodical diagnosis will probably elude me. For this job I'll likely change the harmonic balancer, tensioner, idlers, belts, water pump and supercharger coupler while I'm in there. The car has 173K miles and none of this stuff has been changed. But the engine has had synthetic oil it's whole life and burns very little. The transmission has had regular fluid changes and is showing no signs of trouble. The suspension was completely rebuilt with Bilstein struts, new springs, control arms, tie rods, sway bar links, etc.

The plan is for my son to drive it until he graduates college, which could be six years as he starts his senior year of high school this fall. Hope I don't kick myself for diving in and replacing all this stuff, about $500 in parts from the online GM dealer.