I have a 1992 Chevy Silverado 3500 with 28000 original miles. It runs fine as long as the A/C is off. If I run the A/C on a day where the temperature reaches 104+ the engine will stall and cannot be restarted for at least 30 minutes. I have taken the pickup to several shops but they are clueless.
I contacted an A/C “pro” who said to “bring it in when it stalls.” I’m not exactly sure how I would do that since I can’t drive it.
Anyway, any suggestions?
Will the engine stall if you are cruising at 70 mph with the AC on? Or does the stall occur when the engine is idling?
Which engine is in the truck?
Yes to both questions. The engine is a 350.
Is the humidity high when the engine stalls? I recall a problem with condensation from the AC suction line dripping on the distributor on some Chevrolet pickup engines several years ago.
I don’t think so. The pickup is in Fresno CA where it gets hot but not too humid.
This is a stretch but has the fuel filter ever been replaced. A restricted fuel filter could hold the pressure below the threshold to open the relief valve and allow the fuel line to vapor lock.
I have not replaced it in the 5 years I’ve had the pickup. I will have it replaced and let you know.
Does it stall right away or does it take a few minutes of AC?
I think some electronic component is failing when it gets really hot under the hood.
Maybe the ignition module or crank/cam position sensor.
The last time this happened I thought I was ok until the temperature got to around 104. I had been driving with the A/C on most of the day. I also think it has something to do with the heat under the hood but no one I have taken it to has a clue. I’ll have those items checked and replace the fuel filter.
Perhaps when hot the AC compressor shaft is binding.