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low coolant light flashing


gtoed1969
09-10-2009, 06:57 PM
I had a broken hose the other day and ran the coolant pretty changed the hose and refilled the coolant and now he low coolant light is flashing off and on. How can I correct this problem?

roadrunner2
09-10-2009, 09:06 PM
I had a broken hose the other day and ran the coolant pretty changed the hose and refilled the coolant and now he low coolant light is flashing off and on. How can I correct this problem?

Ran the coolant low?

There may not be enough coolant in the reservoir or perhaps there is air in the cooling system.

gtoed1969
09-11-2009, 05:22 PM
the reservoir is at the correct level. how do you get the air out?

roadrunner2
09-11-2009, 09:05 PM
the reservoir is at the correct level. how do you get the air out?

One way is to wait it out. What I mean is any air in the cooling system is 'burped' out via the reservoir as the engine cools.

When the engine is cold, remove the rad cap, start the engine and let it idle.

Watch the coolant while it circulates through the rad, if there is a bit of air in there it usually comes up as bubbles.
Let the engine run for a few minutes so as to allow enough coolant to flow through the heater core too.
Turn the heater to high heat.

gearhead514.2008
10-04-2009, 06:47 PM
I'm guessing you have a pontiac montana since this is the column for it. The low coolant sensor on these vehicles is mounted on the side of the radiator just below the radiator cap. There is a 2 wire plug that connects to it. Check the fluid level first by taking the cap off. You could have air in the radiator that needs to get out. If the radiator is full of coolant, then you have a dirty sensor. To clean it, you need to unplug the harness and then remove the metal clip that holds the sensor in. There is an o-ring fitting on this sensor to keep it sealed. You should be able to reuse it. Pull the sensor out and have a rag or something else that can plug the hole for a few minutes while you clean it. This is where a friend comes in handy. Have them plug the hole with their finger while you clean it. Anyways, clean off the two prongs on the sensor so that you can see bare metal. The prongs get corroded over time so the coolant does not complete the electrical connection between the prongs. Clean the o-ring and then stick it back in. Put everything back together and test it. It should stay off now as long as you have coolant in it. If you are low on coolant and think you have air in the system, there are 2 bleeding screws on the cooling system. One is on the thermostat housing and the other is on the steel tube coming from the top of the water pump. Both are easy to get to and right on top. Just use a small socket. Run the engine to normal operating temperature so that the thermostat is open and then turn the bleeder screws loose until all air escapes and coolant comes out. DO NOT remove the screws all the way as you will have hot coolant spraying you in the face. You only need to turn it a little until you hear air escaping or you see coolant coming out with no air bubbles. This will get rid of all air bubbles. Do this a couple of times on both bleeder screws and you should be good. Good luck.

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