Low Coolant Light Question

[wildwes1692]

I have a 99 grand prix with a 3.1 engine. My low coolant light came on, so I added some coolant, but the light just blinks every couple of seconds. I reffered to the manual and it states that the light will come on and stay on if the coolant level is low. But mine comes on and blinks every few seconds. Any one have an idea what that means. thank you

[JoeJoe231455]

It may me your sensor is messed up, or that you have air pockets in your cooling system. Have you bled the air from the system when the engine is warm? You have to do that any time you add coolant or service the cooling system.

[wildwes1692]

thank you JoeJoe

[BIG-L]

You have to do that any time you add coolant or service the cooling system.

Wizbang from the ZZP camp said that as long as the bottle is up to the correct level and you have driven it for awhile then it sould have removed all the air and to not worry about it...sounds like it maybe time to replace the sensor....try tapping on it with a screw driver and see if the contact cleans up and stops flashing.

~Larry~

[richtazz]

is your sensor in the radiator or overflow tank. The radiator mounted sensors are optical, and the lens can get mucked up with sludge. The overflow mounted sensor has a float, which can get weighted down by sludge buildup. And we all know how Dex-Cool loves to sludge up as it gets older. Try cleaning the sensor before replacing it.

[wildwes1692]

thanks for your help

[Moser28]

I have a 99 GT 3.8 and the low coolant light will not come on until the thermostat opens. I know this because I have chased this problem for months. There is no air in the system. I think it has to be a sensor because that is the only thing I haven't checked. Where is the sensor in the overflow tank? Do I have to take the tank out to get to it? I know where the one is on the radiator.