I have a 1996 S10 Blazer V6, which has got me stumped.

When I drive my truck and get stuck in traffic where the truck is idling for an extended amount of time (4 or 5 min) it will stall out when I hit the gas. After the vehicle stalls it is very hard to start, I usually shut everything off (radio, air conditioner, etc.) and then have to pump the gas peddle and try to turn the engine over several times before it fires up. Normally the vehicle runs great, except in times where it idles for awhile. In order to rectify the problem, I had a tune up done on the truck, had the throttle body cleaned out, but still no luck. My local mechanic says there are no error codes.

Does anyone have any thoughts? Thank you!

 

My other vehicle used to have simliar symptoms, it turned out to be a vacuum leak. Sounds to me like a valve isn't working once the vehicle has reached normal temps. Not having an error code makes me wonder, but then again, the things I ended up associating to this were:

I would look at PCV valve, just remove and shake, if it rattles, it's likely it still works, if plugged clean out or better to just replace ~2.90 part
Check all valve hoses and connections for leaks, actually run you fingers along the hoses and feel for cracks and slits. Or spray along hoses with a carb cleaner, if idle changes you found your leak (didn't work for me, I had to feel it). Vaccum harness ~$35-40...

Bad fuel pressure. My '95 has a schrader valve on top of engine near firewall, have it pressure tested ~$30-40 gauge, or someone may do it for you for free or a cost. $80-90 fix if you replace the fuel pump and strainer yourself...plus proper tools

EGR valve - (Still no error codes makes this a pure guess) Gets or is stuck open. Makes a vehicle idle rough and diesel sometimes as well...

All these can be fixed by a DIY'r but I'd make sure I had the proper tools and room to work... There are a lot of other more knowledgeble than me on here that will probably chime in with other, more likely, suggested troubleshooting ideas