well the low coolant light's on now on my 98 cavalier winter car- checked coolant, not very low, but add some anyways up to the line. start the car up and take it for a drive, still on. the temperature is fine. could this be a bad sensor or something? (yes i know it's a question about a cavalier, but at least it's still a chevy right?)

 

FWIW, when I changed the thermo, knock module, and had my computer reprogrammed on my 95 ImpalaSS, I pulled all the fluid out and it actually took about 4 starts before the low coolant light went out. If I remember correctly, the manual backed this up. I was concerned also and checked the book to make sure it was a low coolant light. I KNEW it was full. I just filled it, why would the light be on? At least check the manual before you start changing things.

 

If you look at the coolant tank towards the front of the vehicle at the bottom of the tank there is an electrical connector. That is the sensor for the low coolant light. Lightly wrap on the housing where the connector goes in I bet that the float inside is stuck. Hope that helps!

 

you gots air in your system....

check your bleeders, there should be a black bar that comes up from your engine from the left to the right and it disapears into hoses. theres a small nut on it. then on the right side of the engine there is another bolt just like it. its tiny man, run your system for about 10 min then loosen the bolts a little till liquid comes out. i had a cavalier and this was the problem. it worked though!

 

I had the same problem and I changed the sensor (not an expensive part) than gave it a couple gentle taps on the sensor housing as suggested by gearhead86 and it worked. Thank you gearhead86 for stating where the float was positioned.

 

Nice post , you just made a comment on a 03 thread

 

Yep , 15 years old , a few more years and this thread can join the Army