Pontiac Repair: Low coolant light 1995 Grand Prix SE, coolant level, temperature gauge

Question
I have had a low coolant light on for about a month. Coolant level is not low. Temperature gauge has been fine until yesterday, started acting funny. It would go to the red when I first start the car and then come down. It was doing this all the way home. Got home and my daughters boyfriend found a leak in the water pump. He put a new water pump on. Temp gauge is still acting crazy and low coolant light still on. Do you think the thermostat could be bad??? Why is my low coolant light on and my temp gauge acting crazy?

Answer
Hi Dana:

the low coolant light is on more than likely because the probe/sensor in the radiator is bad that controls the lamp on the dash. It's a pretty common problem on those older cars. as for the temp gauge acting up it was more than likely due to air in the system beacsue it's low of coolant or was low on coolant. that engine has a tendenct of getting an air pocket stuck in it and that air in the system makes the gause act funny. ther are 2 air blooe screws on this engine one on the thermostat housing and one on the heater pipe that runs across the front heater pipe over the radiator. get the car up to opertaing temp but not hot with it running open those bleeders up one at a time untill the air is gone and antifreeze starts to come out. then do the other one. Let the car cool down and then top off the radiator and the coolant overflow tank and that should do it. Hopefully to didn't overheat the engine and cause damage to it. good luck :}