I have an 87 Z-28 that compeltly shuts down just above 220 degrees. I haven't yet checked to see if a loose spark is the problem, but i doubt that, seeing as how the engine runs perfectly under 220. My father believes it's the electronics, and my friends tell me to get a cooler thermostat. I've heard talk of a heat soak problem. What is that, and what could be wrong w/ the engine to make it shut off as such?

Heat soak is a problem with the starter motor itself, usually. It is a condition where the engine will not crank at all for several minutes, up to several hours after being shut off, i.e. when its hot. It almost sounds like you are running too hot. I've heard these cars (I think it was sometime in the later 80s) have a thermal safety built into them to completely shut them down at or above 220 degrees. Try a cooler thermostat to see if thats the problem.

Hope this helps,

Camaro350

GM had a real problem with "hot soak surge" in the mid to late 80's. At the dealership we had a "fix" for it that invovled heat insulators/jets/and even a small fan that blew cool air on the carb fuel line/filter area. But yours sounds more like electrical. The ignition module in the distributor is heat sensitive and may be your problem. Also, the factory "on temp" for electric cooling fans is about 220 degrees.In extreme conditions the charging system may not be up to it and "shuts down" engine when the fans are trying to come on. Hope this helps. http://hometown.aol.com/zz430droptop67rs

[This message has been edited by ZZ430DropTop67RS (edited 05-24-2001).]

Hey,
I'm going to put in a cooler thermostat. Some mechanics told me it was the sensor shuting the engine off around 220. I'm going to eventually get a new firing module. Thanks for your help.