Attention: TDR Forum Junkies 
It is about 40 deg. outside and my heater just started working intermittently. Now before I start, I know that the truck takes awhile to warm up enough to blow warm air through the vents. That is NOT what I am experiencing now. This thing is blowing ice cold until I have gone about 10 minutes down the highway and then suddenly blows hot rather than gradually warming up like normal. Then if I stop at the store and kill the engine, when I come back out seconds later it's blowing ice cold again. Once again it takes it several minutes to blow warm air. Ice cold then suddenly warm again. Just to see what it would do, on the way home from work today, after the truck (and the heater) warmed up, I pulled off on the shoulder, killed the truck and immediatly restarted it. Same thing-ice cold air from the vents after restarting. The engine is running at normal operating temp. once warmed up. Any ideas? Heater core? Electrical connection? I live in southeast Texas so 40 deg. is the same as -40 deg. to me, so this is kind of a big deal to me right now.
Bryan
Bryan
