Well, it is the first really cold day here in Kansas, and we have experienced a weird thing with either overheating of all things, or the behavior of the temp gauge on a 1983 GL (normally aspirated).

Before there was enough engine heat to warm the air for the heater, my son called to report that his temperature gauge kept going up to the red zone; if he slowed down, it IMMEDIATELY dropped to normal. I had him get off the road and went to where he was. Temp gauge was normal; coolant reservoir full but not overflowing; engine compartment appeared normal, no sign of coolant leaks (new water pump last year), fan working correctly; no bad smells. I followed him and within a half mile, he pulled off the highway with the same symptoms, so I drove the car. Sure enough, when accellerating (moderate engine load) the temp gauge rocketed to the red zone; as soon as I let off the accellerator (and I mean within 1/2 second or a second) the temp gauge began dropping into to the normal zone. If I went uphill, the temp gauge began to climb. ONce I accellerated to speed and just cruised, normal temp. By this time, there was plenty of heat through the heater.

I think this is indicative of a failing temp gauge or temp sensor, not actual overheating; I can't imagine the engine temp fluctuated that wildly that quickly. Any thoughts?

Kurt