Car coolent problem

[Kristi2k]

When driving long distances (2 hours) my coolent burns up, the low coolent will come on and eventually over heat, I then fill it up and drive another two hours and the same thing happens, this does not occur if I drive around town. Nothing is leaking as I park in the same place and see nothing on the ground. What could be the problem?

It's a 2003 Mailub, automatic, 102,000 miles, transmission fluid was changes a year ago, oil changed regularly.

Edit:
While reading through these posts I remembered this:
Almost a year ago I went to the dealership to have the brakes replaced (under warranty from the last time I had them replaced) and the tech stated that the lower intake gasket was leaking. Could this be the problem? At the time I decided not to do anything because they said it was not a "big deal" at the moment.

 

[Quiksilver]

Is the vehicle actually over-heating or is it display just telling you so? Does the vehicle use an electric radiator fan? Also how's the radiator temp <insert name of part I can't think of name of> (usually like 180F rated or whatever).

 

[Kristi2k]

I dont know what type of radiator it is, but yes it's actually over heating, the red light came on and it was boiling.

 

[Bignate603]

That's very odd, usually if you're driving at high speeds the cooling system does better (more air flow over the radiator). I think quiksilvier is thinking about the radiator cap, and I think that's possible. It's possible you've got a partially plugged radiator. Take it to a shop to have them pressure test it. It will show if it's flowing correctly.

 

[Quiksilver]

Aha! I know what I was thinking of before now.

Radiator Thermostat.

I'm thinking that it's borked and not opening up properly when it hits a certain temperature, the result is the engine runs hotter with restricted coolant flow so its not being properly cooled eventually leading to overheating.

My only other ideas are something is blocking cool air getting to the radiator or something in the radiator broke and is no longer functioning correctly.

 

[Bignate603]

Originally posted by: Quiksilver
Aha! I know what I was thinking of before now.

Radiator Thermostat.

I'm thinking that it's borked and not opening up properly when it hits a certain temperature, the result is the engine runs hotter with restricted coolant flow so its not being properly cooled eventually leading to overheating.

My only other ideas are something is blocking cool air getting to the radiator or something in the radiator broke and is no longer functioning correctly.

That's a good point, I forgot about the thermostat. Those things are cheap, and a normal person can put them in without too much fuss. I'd spend the $10 on it and see if it fixes your problem. It's a really cheap thing to try before you take it in to a shop.

 

[Kristi2k]

Even though the coolent is being used right up on long trips? Someone else mentioned a head gasket, are those expensive?

 

[iamwiz82]

The question is, is the coolant boiling out because the car is overheating or is the coolant being burned/leaking out causing the overheating?

Usually the thermostat is easy to get to and it's easy to test. Tie a string to it and lower it into boiling water.

100,000 miles is about the lifespan for a waterpump, as well.

 

[halik]

Originally posted by: iamwiz82
The question is, is the coolant boiling out because the car is overheating or is the coolant being burned/leaking out causing the overheating?

Usually the thermostat is easy to get to and it's easy to test. Tie a string to it and lower it into boiling water.

100,000 miles is about the lifespan for a waterpump, as well.

Right on - if the headgasket is done, you'd see a fair amount of white (not blue) smoke in the exhaust.

I would bet on thermostat not opening, since it only happens on long trips. Driving at speed would keep the temp down since radiator would be getting plenty of airflow. Both the water pump and thermostat are relatively cheap parts - $85 and $8 on my Porsche

 

[Vette73]

Also don't forget the pressure cap. I don?t say radiator cap as on most cars it is on a pressurized overfill tank now. If that is bad then it will not keep the pressure high enough and cause the coolant to boil. Replace that first and see if that helps. If not then replace the thermostat and check your oil and coolant for signs of mixing.

 

[Kristi2k]

I had a friend look at the oil with me, he said it look good, the oil was very brown (the way it normally looks when I put some in). So he things it's probably not the gasket. I think what I may do is take it to a local garage and see if they can check the water pump and that thermistat and also flush out my radiator due to the coolent I HAD to put in that night it over heated not being Dex-cool.

 

[Kristi2k]

I found this, as an FYI
http://www.carcomplaints.com/C..._manifold_gasket.shtml

 

[OdiN]

Thermostat doesn't explain the missing liquid. It's leaking out somewhere - if that much was boiling away you'd see plenty of steam - do you have a lot of steam? Maybe unless you've got a gasket problem.

I would think there has got to be a leak somewhere.

It may not leak just sitting because there is no pressure - after driving it you should be able to find a leak where it's coming out.

 

[herm0016]

the intake gasket is not really common, but is a problem on some 3.1, 3.6 and 3.8L engines. they used a cheaper plastic intake that does not seat as well to the block like a cast aluminum intake would. if caught early it is an easy fix, if you don't catch it a total engine rebuild will be necessary because of the water getting into the oil. its not GM's Fault that people are stupid enough to let something like that go, it is GM's responsibility to fix the gasket though. the symptoms of this will be water in the oil and leakage from the intake to the outside of the motor. Sounds like you need a new thermostat to me.

 

[jaha2000]

The intake leak is VERY common on 3.4.
Plastic gaskets + dex-cool = epic fail.
Just had them replaced on my 03 grand am. Same symptoms, disappearing coolent.
My father works @ a gm dealership, the failure rate is something like 50%. Hence the class action lawsuit...

 

[Kristi2k]

I have the 3.1 V6, The radiator thermostat is $8, I just checked so I'm going to replace that and have a friend take a look at the rest. How can I get in on the lawsuit if possible?

 

[Mxylplyx]

Originally posted by: jaha2000
The intake leak is VERY common on 3.4.
Plastic gaskets + dex-cool = epic fail.
Just had them replaced on my 03 grand am. Same symptoms, disappearing coolent.
My father works @ a gm dealership, the failure rate is something like 50%. Hence the class action lawsuit...

Yep, I had to replace the intake manifold gasket on my 2000 Jimmy a few months ago. Pretty much any car that uses that dex cool shit is going to have the problem.

 

[exdeath]

If you ran the coolant low the first time for whatever reason (bad cap, bad thermostat or fan problem causing boil over past cap, etc) you now have air pockets in the system and need to refill and burp the cooling system completely. You'll need to address that before trying to find what the original problem was. The 3100 is notorious for cooling problems.

Find the steel coolant tube at the top of the engine that has a square plug and open it up, along with the pressure cap. Start the engine while it's cold and slowly add coolant until you see a steady flow of coolant streaming from the plug (not sputtering or spraying) and verify the tank is filled to the line and not over.

 

[Kristi2k]

While reading through these posts I remembered this:
Almost a year ago I went to the dealership to have the brakes replaced (under warranty from the last time I had them replaced) and the tech stated that the lower intake gasket was leaking. Could this be the problem? At the time I decided not to do anything because they said it was not a "big deal" at the moment.

 

[mooseracing]

Originally posted by: herm0016
the intake gasket is not really common, but is a problem on some 3.1, 3.6 and 3.8L engines. they used a cheaper plastic intake that does not seat as well to the block like a cast aluminum intake would. .

It's so uncommon they offered to pay the repair bill


It's not a plastic intake issue its a dex-cool easting teh gasket issue.


I posted a month or more ago on the latest recall and where to file your claim.


OP get it fixed, I would bet your car is eating the coolant, unless you see it leak after you park.

 

[Kristi2k]

Moose, Is it possible that GM pays for my bill as well?

 

[OdiN]

http://www.girardgibbs.com/dexcool.html

 

[dsity]

Terms of the Settlement:

You may be eligible to receive between $50 and $800 in cash reimbursement under the settlement if you have paid for a covered repair by May 30, 2008, and if you submit a claim by October 27, 2008. If you paid for multiple covered repairs, you may be eligible to receive multiple cash reimbursements provided you submit a separate claim for each repair.