1999 Pontiac Grand Am Low Coolant Light?

[GaryO]

My sister's car, a 1999 Pontiac Grand Am with the 3.4 engine is driving us nuts. The low coolant light keeps coming on and chiming even though fluid level is correct.

I read about the service bulletin # 04-06-02-007 regarding the issue. I disconnect the sensor and the light goes off. The bulletin states to clean the sensor, but this thing has a plastic surrounding, which is clean. I can't get inside to the brass part they are talking about.

So, I went and bought the sensor since it was only about $8. Still, the same darn problem!

Where else should I look?

 

[Ungarminh]

I don't mean to revive a thread that is a few weeks old but I thought I should mention that I'm having the same problem. I'm a delivery driver and my low coolant light came on while on delivery. When I got back to the shop, I popped the hood and went to check the coolant level so I loosened the cap a bit and let some of the pressure out and waited for it to cool for a little bit, when I completely took the cap off, me and a buddy looked in and it was to the top. About 5 seconds into looking at it, ALL of my coolant just drained onto the ground. Every bit of it. When it started draining, we were frantically looking for the cause but couldn't find any, my buddy said it looked to him (we were on different sides looking) that it was coming out of the side of the engine. I refilled the reservoir with water and it was leaking a few drops a second for a while and then stopped but my low coolant light is still on, even though it's to the fill line.

Last year, when I bought the car, the low coolant light would come on for no reason then, as well. Had plenty of coolant in the car but it would still come on and stay on. So for after a few months, you just sort of ignore it, big mistake on my part as this time, there WAS a leak and I blew a head gasket and had to get my engine rebuilt (took the mechanic 2 months to do that and he gave me a year warranty). Since I got my car back (February), I've had to take the car back to him 3 separate times to fix the timing chain, as he keeps putting it on wrong and I'm now wondering if he didn't do something right with my water pump or something along those lines.

 

[gmtechs]

as long as the rad is full and bottle , u should not have a problem
but i would start vehicle let sit and make sure the bottle stays full and does not drop down to trun the light on

another problem is those sensors stick