Blazer won't start when hot

[timh059]

Hi all. I have a 94 S-10 Blazer that wont start sometimes when it's hot. Engine turns over just fine, it just wont fire up. Checked for spark, thats fine. I am getting gas, too. Is there some valve or something that can cut off air to the engine if not working properly? When it does this, it's been driven to operating temp and then turned off (to run into the store, etc.) I live in Minnesota and I didn't have this problem all winter, it just started cropping up since the weather has gotten warmer. The fuel injector assembly has been replaced twice in the last 3 years, so I hope it's not that again! I have the 4.3L 6-cyl, engine code W, 4 wheel drive. No check engine light comes on, no codes get stored. I'm sort of at a loss. If I wait long enough, the engine will eventually start, but the wait time seems to be getting longer. Any insight would be greatly appreciated.

[Superdawg]

I don't know much about mechanics, but I know that if the mass air-flow sensor isn't sensing enough air, it won't run. Check that. I am sure you have the vortec, so I'm pretty sure it has that.

[pcv]

You need to scan the vehicle to see which sensor on the car is out of specs. I suspect you might have a bad coolant sensor, throtle position sensor or even an egr valve. Normally a bad erg valve will back fire at times. Good Luck to you.

[Superdawg]

Originally posted by pcv
throtle position sensor

I had that go on my truck. What was happening, was while trying to shift from first to second, it would slam into gear, but would run fine after that. Then, if I were sitting on a hill, in drive. And rolled up the hill, but had a little bit of backroll. If I revved it to roll forward, it would stall on the backroll. Not always, but it did.