1997 blazer stalls in traffic. It only does it on hot days in town when we use the ac or if the temp gauge reaches 210. We had the ignition control module checked and the catalytic converter is fine also. We have recently changed mass inflow sensor. It isn't throwing a code.If we let it cool it goes back to running fine. Any suggestions.

 

I would definitely check the ignition system out. The coil & ignition control module can both cause heat related shutdowns. 210*F isn't that terribly high for a hot day with the A/C on so long as it isn't climbing past that.

 

Ok checked the icm and coil they r fine. Yesterday we went to a town about an hour and a half away it did ok at first. Then traffic got bad because of an accident same thing, it reached temp and sure enough started stalling. So when we finally got back after stalling and stopping to let it cool some we flushed the radiator, put in a new thermostat added new coolant and sealant just to be on the safe side. There was a lot of rust. It acted up at first but we drove it to town and it seemed fine after that but it was cooler outside. The real test will be when it is hot and we go back to town. Do you have any other suggestions if this doesn't work? Should we clean the EGR valve?

 

Hmmm Still sounds electrical to me-GM coils may test out fine,but fail under high-heat scenarios as you described;same for modules...Replace both,check your cap&rotor.wires & plugs=and replace them as needed. And inspect all under-hood wiring connectors.inproper removal&replacement of the retainers can be an issue as well!

 

You really need to carry the test procedure & a multimeter around with you. When the truck stalls, test it then and there. As step66 stated, heat/load induces the failure.

 

When does it stall? When youre sitting still idles in gear? creeping along? Does it restart immediately or does it need to cool for a while? if so, how long? I know it seems like strange questions, but I am trying to picture this in my head.

 

It stalls mostly right after accelerating, after sitting at a stop light or stop sign. It will also stall just going down the road at speed. It will start right back and sit and idle but as soon we put it in gear and it starts stalling, sometimes it will go immediately but if we don't let it cool it will just keep doing it until we get where we are going. Once we get out of town traffic it doesn't do it. Someone said they thought it was the fuel pump, but it only does this when it reaches temps. between 190 and 210.

 

Ok, the theory I was going to suggest doesnt fit. Sorry I didnt have a quick easy answer

 

Mine is a 99 the same problem I think . It doesnt matter if you are on or off the gas . you start through an intersection and it dies ,you can be cruising at lower speeds and boom dead .only on hot days or if it sitts idling for a couple of minutes . Its undoubtedly a heat issue . I thought the ignition coil so i replaced it . It didn't help .It is just like you turned the key off however the instrument panel and tack continues to read till the engine physically stops . Icould use help too .All I know is it isn't the coil .

 

Does your Airbag light, Security light and Abs light come on or flicker before it stalls?
I just read the dates, you need to start a new thread.