I have a 1994 chevy s10 blazer4.3vortec w vin. After driving for 20-30 minutes it misses out as if its out of gas and dies. The check engine light doesnt come on at all!!! The blazer will start after it cools off a lil but will die again. If i let it completely cool off it will run for 20-30 minutes and do the same thing. when it dies i can turn the key on and off and still hear the fuel pump kick on and off. I have very little cash and cant afford to replace this and that. Can someone please help??????Please

 

Honestly it sounds like when the pump heats up it doesnt pump like it should. You need to get the fuel pressure checked. Must be at least 60 psi and hold above 52ish for 10 minutes. Check it at the engine,then double check it at the inlet of the fuel filter. You can get a free fuel pressure kit (loaner tools) at autozone,but you have to leave a deposit(so if you never bring it back,its paid for) you get every penny back when you return it.

 

Any time you're having temperature-related driveability issues check the ignition system. Take the ignition control module out of the truck and have it tested at your local auto parts store.

Also test the fuel pump relay. They can go bad over time. It's not as common on Blazers as it is on other vehicles (Hondas come to mind) but it is a possibility.

 

Does it have a good steady flow out the tail pipe or is it real weak. Without it being hot can you take the palm of your hand and stop the flow or does it push your hand off.
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I'm leaning towards the ingition mod also but running everything by ya.

 

the exhaust is really weak...recently i thought the problem was due to a clogged up cat, so i removed it and put in just straight pipe but nothing changed. My fuel pump sounds healthy and still kicks on when the truck wont move.

 

Your fuel pump can come on even when it's weak. I had a '94 Jimmy a few years ago and the fuel pump died. It would still come on but it only produced 35psi which isn't enough to get the injectors to fire. You need an actual pressure test to know whether it's producing proper pressure. Check the pressure at the engine. If it won't get up to 60psi and hold at least 52psi for ten minutes then the pump needs to be replaced.

Once you've ruled the pump in or out as a cause of the problem then you can proceed with further diagnosis.

 

just remember to check it at the engine,then at the inlet of the fuel filter. if it drops at the engine,but not the filter,its the fuel regulator. if it drops at both...say hello to new pump

 

Maybe your coil is getting hot. I had one do the same thing, once the coil cooled off it would run fine. After a few minutes it would die and not start back. I would check it out

 

Do you have a tach?

Watch the tach when you are cranking. See it bounce a little before it starts? When it quits, watch tach.. no bounce = bad ign module or distr pickup. Wont reflect bad coil, though.
OFTEN bad coil will show by engine falling on face at certain rpm, no matter how you feather the throttle. In your case, bad coil might result in ever lower trip in rpm as it warms.

 

I remember something about a temp semsor causing problems like this, once your truck warms up with a bad temp sensor it dies.