My sons Model 2000, Blazer 4.3 liter is not starting. One minute its fine the next its not. How do you diagnose if this is a firing issue or a fuel problem? He’s away at school and I’m trying to avoid a huge bill.

 

When you say it's not starting, what is it doing? Is it turning over fine and just not firing? Can you dribble fuel down the throttle body (after disconnecting the MAF sensor electrical connection & the intake duct work at the throttle body) and have it catch and run for a bit until the fuel is burned off?

 

Correct it’s turning over but not firing. I'm troubleshooting with my son who's away at school so I have not been able to look at it. However its been sitting over night and most likely will start right up. That’s what's so confusing, this tend s to be an intermittent problem.

 

Does the security light come on when it isn't starting? It could be an ignition switch failure.

 

My son just called started right up. ??? I don’t believe this is temperature related due the fact he try tp start this late last night after it sat for hours. The Security light does'nt come on when the car isn't starting

 

he try this and the car started right up