I have a '96 Blazer 2 X4 V6. 175,000 miles.

After I drive it for about 20 minutes to 1/2 an hour the engine starts to bog down, it sputters out and stalls. Than I cannot get it started again. After letting it set overnight, it starts right up and acts fine. It stalls sooner if the weather is warmer out.

I have had the fuel pump replaced about 2 months ago.
The spider injector assembly was replaced 2 years ago.
The tranny was rebuilt about 350 miles ago!

The shop said it threw 7 codes, but is running fine this morning.

HELP!!

 

My 19 4.3cpi was doing the same thing. I replaced the pickup coil, icm, plugs, wires, cap, rotor, tps, fuel filter, ecm, and tested coil and fuel pressure. It still died after warming up. Also it was not throwing any codes. Needless to say I was frustrated.
I decided it had to be fuel related after reading an article about cpi problems. Here is the link. http://www.tomorrowstechnician.com/a...injection.aspx When I opened the upper intake I found the passenger side of the intake squeaky clean and the other side crusty. That ment fuel was leaking out of the pressure regulator. The electrical connecter was soaked. The connection was shorting out when it got hot and shuttig down the fuel.
I replaced the spyder and YEAH, it runs like a new rig.
Good luck

 

20-30 minutes is about how long it takes to get the engine up to normal operating temp. At that point your emission systems kick in and adjust the engines performance based on the sensor readings.

Disconnect your upstream O2 sensors a see what happens. This is not a fix, without the O2 sensors your fuel mileage will suck big time. However if the engine purs like a kitten and keeps running your narrowed down your problem to the emission system.

Before you do the O2 test, take your ICM into your local autoparts store and ahve them test it. Typeically when the Ignition Control Modual (ICM) is on its last legs it will quit working when it gets hot, after about 20-30 mintues of driving.