1998 Pontiac Grand Prix

Engine Cooling problem
1998 Pontiac Grand Prix 6 cyl Front Wheel Drive Automatic 255000 miles

My car is consuming alot of antifreeze, adding coolant several times a month. My temp gauge is way above normal and the low coolant light comes on even when its coolant in the vehicle. Its not leaking when sitting still and when the heat is on the guage is within normal range.
I had the thermostat replaced and coolant switch replaced.
September 9, 2010.

Is there any evidence of coolant leaking under the vehicle? Have you checked to make sure the engine oil and trans fluid are not contaminated with coolant? Is there white smoke that comes from the exhaust of the vehicle?

Let me know.


There is no coolant leak underneath car. I checked the oil and tranny fluid and didn't notice anything abnormal, fluids are of normal color. No smoke coming from either pipe.
It does look as if the fluid flowing into resevoir from radiator is more water than coolant. (Or could just be me).
The gauge hand used to read normal levels before I had t-stat, thermo switch and resevoir replaced.

Sep 10, 2010.
I wonder if the t-stat was put in upside down. It this didn't happen until the work was done, that is possible.

I just noticed today that after I run the heater on low to keep gauge low, there is a drip comming from underneath passenger side of car after its parked and turned off. No coolant, just water. I" ll check to see if t stat is put n wrong.

Sep 11, 2010.
When you run the heater, is the AC turning on? Do you have it on defroster?

Let me know what you find.