Car rejecting water/coolant...

Yesterday my "Low coolant" light came on.. NOTE: It did not over heat, But the needle was just a tad over 200. So I quickly pulled into a garage... they added water, within a minute the water was rushing out of the resovoir tank.. They said it was my thermostat sticking and it needs replaced. However, my car is at their garage as of right now.. I just wanted someone's input on my situation. Could their be another problem other than the thermostat?

1999 grand am GT.
3400 SFI.

I really don't think you have a problem with the thermostat. It sounds like when the water mixed with the hot coolant that it instantly boiled and came out of the reservoir. Changing the thermostat won't hurt anything next time you add coolant make sure it is a mixture of 50% water and 50% antifreeze.

well.. what caused the car to overheat to begin with? It was getting hot and the coolant was overflowing from the bottle while I was driving..

Even before I pulled into that station.. the resovoir tank was empty..
Note: I just filled it with dexcool a few days before that.. so I know for a fact it was full..


I really don't think you have a problem with the thermostat. It sounds like when the water mixed with the hot coolant that it instantly boiled and came out of the reservoir. Changing the thermostat won't hurt anything next time you add coolant make sure it is a mixture of 50% water and 50% antifreeze.

I added coolant to my tank once also and later that day or days later (can't remember) I noticed steam coming from my hood. Got out, looked around, saw coolant all over the ground, all over the engine. Lesson learned is that the coolant tank cap must be screwed on extremely tight. I think I just put the cap on with a little budge. From now on, I use brute force on that sucker. It is a 2003 V6. I posted this because you said you added coolant a few days before. You might have just not put the cap on very tight.

well.. the garage just called me and it's the "intake valve" that is bad and it's causing it to overheat the motor... he said it would cost roughly $500.00
to repair.

No way its the stat, and if it were it'd be cheap .. $10-$15 + labor

Im sure you'll get more input on this from some more people, it seems like they're just looking for something to do =\

$500 could be saved =p

In your first post you didn't say that it overheated. The 200 degrees that you say is in no way considered an overheat condition. I also don't know what the garage it talking about when they state the intake valve. Can someone give me a better description as the only intake valves I am aware of lie in the heads and work inside the combustion chambers. The book I have discusses the heater coolant inlet pipe but no intake valve. Must be another one of those GM innovations!!

I'm sorry.. I meant to say "Intake gasket" not "intake valve" :screwy:

My temp gauge was slightly above 200 when my --low coolant-- light came on and coolant was rushing out of the resovoir bottle. A friend of mine recommnended me to his friend. He said that job is not that hard to repair the Intake gasket. The total bill would be $350.00. The first garage wanted $500.00

My question is... if my car didn't overheat what was causing the coolant to spray out of the resovoir bottle??? It was spraying out of the cap and out of the hose.. Like I said before.. the tempature gauge went slightly passed 200 degrees. I don't consider that overheating. I am baffled.

In your first post you didn't say that it overheated. The 200 degrees that you say is in no way considered an overheat condition. I also don't know what the garage it talking about when they state the intake valve. Can someone give me a better description as the only intake valves I am aware of lie in the heads and work inside the combustion chambers. The book I have discusses the heater coolant inlet pipe but no intake valve. Must be another one of those GM innovations!!

My question is... if my car didn't overheat what was causing the coolant to spray out of the resovoir bottle??? It was spraying out of the cap and out of the hose.. Like I said before.. the tempature gauge went slightly passed 200 degrees. I don't consider that overheating. I am baffled.

A poorly put on cap or the inside threading has gone to waste.. new cap should be around $15 or so...

Dont see how the intake gasket would effect spewing of the resovior and top.... when water is boiled it creates steam and gas and expands kinda like a kettle pot... ur coolant res = kettle pot :D

Something with the garage sounds fishy, change the thermostat yourself with one from a dealer or the best Napa has, fill the coolant up, run while sitting in one place (watch the coolant level and engine temp to get all of the air out of the system). Then keep a close eye on your coolant level (check every day) and keep a close eye on the coolant temp when driving (don't let it get above 235 deg once you get the system purged of air) (200 is a normal temp for the thermostat to open at, 210 degree the fans kick on).

If you have an intake gasket leaking your either going to get oil in the water, or see it under the intake (or a film from the coolant evaporating red if your using dexcool). If you want to check your orig thermostat drop it in some boiling water to see if it opens (210 deg +), not a bad idea to check the new one before installing (but I never have).

Sounds like the garage is slow and trying to make more work.

Ok, so here it is... Simple problem, major headache.. My resovoir bottle cap was shot. he replaced it and I am no longer loosing coolant from the resovoir bottle. My engine wasn't building pressure. BUT the bad news is.. My Upper and lower intake gaskets still needed replaced. Of course I knew that because I saw the puddle of antifreeze laying in the engine..

Intake gaskets + thermostat = $425.00

He said he'd better change the thermostat just to be sure..

Now my next question is.. My car takes that Pink dexcool antifreeze.. he put in the green 50/50 antifreeze from Advance auto. Is this another major issue on the rise?

Stay with the extended life antifreeze. Try the Prestone Extended Life as it is a much better product than dex and you won't have to deal with any issues related to dexcool in the future.