Low Coolant light on Dash

[Ferny_71]

I have a 1998 Montana and recently the light of the Low Coolant appears ON, I checked the level of the coolant and is OK.
The light is ON and OFF. Also some times the light is off and during some miles driving the light is ON.
can somebody help me?

[catesja]

I would open the bleeder screws and let some coolant run out while filling the radiator directly. (Be sure the van is cool!) Then after you see coolant at the bleeders, close them and fill the radiator full. THen full the overflow resevoir to the full cold line.

It flashes or goes on and off, because the coolant sloshes in the tank and it may hit just right to trigger it off, or on!

[kcarlen]

I posted about 6 months ago the EXACT SAME PROBLEM.

If you are lucky, it will be low coolant.
If you are like about 5000 other people out there, your HEAD GASKET is leaking, and it will be about 3 days before your engine will totally overheat.

They will first say to bleed the system, then to replace a "faulty" coolant sensor, then proceed to replace the Waterpump, then will say, you know what??? the Head gaskets need to be replaced, along with the INTAKE GASKET.
You are looking at about 2500 CAD.
I negotiated to 2000.

This is a known issue with the 3.4L engine.
Good luck, do-not rely on this vehicle until you are in the clear.

Best of luck, let us all know the outcome@!

[rkvons]

Don't panic just yet. If the level of your coolant is low enough, the low coolant light will go on and off while driving because your engine is heating up and cooling off. When it gets hot, the expanded coolant fills your overflow reservior, turning the low-coolant light off. When your engine cools, as it does when coasting downhill for example, it sucks coolant back in from the reservior, thus turning the low-coolant light back on. To see if you have coolant in your oil, see if your oil is clear and at the right level on your dipstick. If you have coolant in there, it will be frothy and brown. Make sure your vehicle is level when checking the coolant level.

-Rick

[Ferny_71]

I opened the bleeder screws and let out some coolant and fill the radiator full and the resevoir and still the light is flashing on and off.
Could be a fuse or electrical connector?

[kcarlen]

Originally Posted by Ferny_71

I opened the bleeder screws and let out some coolant and fill the radiator full and the resevoir and still the light is flashing on and off.
Could be a fuse or electrical connector?

I will explain simply what is happening.
The fluid is now going to get extemely hot, as gasses are now exposed slightly from your now worn out head gasket. This gas escapes from your combustion chamber and makes pockets of air (Bubbles) in your system, that is why people have asked you to attempt to bleed your system, in hopes of removing the air pockets.
The air pockets are just that, an absence of liquid. This is why your sensor is flashing on and off at random.
The only way to cure this is to have a mechanic do a leak test first. If you are driving the vehicle everyday, you most likely only have days left before your whole system overheats.
This is one of the most common problems with the GM 3.4/3.1 motors.
Do not rely on this motor until you have fixed the problem, which I have stated in a previous post.....will most likely cost you a couple thousand.
Good luck!
I have heard that there is something on the market that will plug the leaky gasket if it is not too far gone...