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Overheating issue

Below Average Joe

New member
I have a 03 GP GT and I am having overheating issues. It has done this in the past and changing the tstat usually work. this time changing the tstat did not help. Any suggestions on how to fix this? I had an old guy tell me that I need to have my system flushed and it should fix this problem. I have never had the syatem flushed since I have owned the car (5yrs) It is my dd so it needs fixed soon. Please help???
 


I dont know if getting a flush will fix the problem. You should get a flush anyways to get the orange GM dexcool out of the system. Have them refill it with the standard green coolant. GM Dexcool is known for leaving large amounts of sludge at the bottom of the radiator.
 
I dont know if getting a flush will fix the problem. You should get a flush anyways to get the orange GM dexcool out of the system. Have them refill it with the standard green coolant. GM Dexcool is known for leaving large amounts of sludge at the bottom of the radiator.


Thanks. Do you have any suggestions about the overheating?
 
Have you maintained the coolant and had it changed out at the 5yr or 150K miles as expected?

Is there sludge on your radiator cap?
 
Have you maintained the coolant and had it changed out at the 5yr or 150K miles as expected?

Is there sludge on your radiator cap?

I haven't changed the coolant since i have owned the car. It only has 127k., but changing the thermostat i noticed the coolant was a rust color. Would this casue it to overheat? This is the 3rd or 4th thermostat I have changed since owning the car. I am not to sure on certain areas of the engine and really don't want to screw soemthing up. We can't afford for one of our cars being out of commission.
 


Ok, then lets rule out a sludged up radiator.


I am guessing it would be best if i flushed it out anyway. Since the tstat is new, what could be the problem then? I am new at trying to fix these types of things to save costs. I am trying to read everything on this forum to make myself aware of what to do if problems arise.
 
Since you just changed the t-stat, did you bleed the cooling system properly? Might just have some air trapped in it.
 


Since you just changed the t-stat, did you bleed the cooling system properly? Might just have some air trapped in it.


The reason for changing the tstat is because of this problem. I would think this if it did not do this before. I have been reading up on this situation and it seems like to bleed off any air is to open the radiator cap and turn the valve on the tstat housing until antifreeze runs out. Is this correct?

I did replace the old one with a 180*
 
Correct. Let the car come up to temp with the cap off and fill as needed while running. As soon as it gets to the point where it wants to spit it out then I cap it and crack the bleed screw on the t-stat neck and wait for the air to get pushed out from there. Then close the valve and let it cool down and re-check your levels in the rad and the overflow. Fill as needed. You may have to bleed it again using just the screw to get it all out. These cars are known to be difficult sometimes.

And from what I know a 180 stat in a stock tuned car will not net you any benefits, and may acutally hurt your mileage as the motor is not getting up to the proper temp internally. That and your fans are still tuned to come on around 210 no matter what the t-stat says.

And you say you smelled coolant when you parked it? That right there would tell me there is a leak somewhere which means you could be getting air in the system from that as well. Probably a leaking coolant elbow on the pass. side of the motor. Track down that leak, unless you spilled some coolant while changing the t-stat, then it could be that burning off.
 
Correct. Let the car come up to temp with the cap off and fill as needed while running. As soon as it gets to the point where it wants to spit it out then I cap it and crack the bleed screw on the t-stat neck and wait for the air to get pushed out from there. Then close the valve and let it cool down and re-check your levels in the rad and the overflow. Fill as needed. You may have to bleed it again using just the screw to get it all out. These cars are known to be difficult sometimes.

And from what I know a 180 stat in a stock tuned car will not net you any benefits, and may acutally hurt your mileage as the motor is not getting up to the proper temp internally. That and your fans are still tuned to come on around 210 no matter what the t-stat says.

And you say you smelled coolant when you parked it? That right there would tell me there is a leak somewhere which means you could be getting air in the system from that as well. Probably a leaking coolant elbow on the pass. side of the motor. Track down that leak, unless you spilled some coolant while changing the t-stat, then it could be that burning off.

Thanks for the information. I took it home last night and jacked it up so i could look underneath it. I couldn't find any leaks. I do however remember having a coolant elbow on the passanger side this summer. After looking under it and not finding anything wrong I started to look at coolent elbows. No leaks. I am guessing spill that was burning off (smell). I let the car warm up and opened the overflow and loosened the readiator cap. A big sound of air came from the overflow. After that the car runs at normal temp?? I am not sure what fixed it, but it is fixed as far as i can tell. I am still going to have it flushed though. Would it be best to have it tuned without any performence parts? I am getting pretty bad milage as it sits. i am going to do the usual tune-up after we get my wifes car sold.

On another topic. I have had a small oil leak for a year or so. I havent seen any spots when it is parked. While I had it up last night i looked to see where the oil may be coming from. It appears that between the oil pan and what i am guessing is the ?trans pan? is covered with oil. Any suggestions.
 
Ignore that oil leak if it's small. You have to pull either the trans or engine to fix that. Typically it's the rear engine cover gasket or the rear main seal.
 
Ignore that oil leak if it's small. You have to pull either the trans or engine to fix that. Typically it's the rear engine cover gasket or the rear main seal.

Ok thanks. I was going to have my mechanic look at it Friday. The Ford guy was saying the 180* tstat will hurt if i am running a stock tune. Is this true? If so, can I have it tuned with not running any aftermarket goodies?
 


Courtesy of BillBoost via a search:

Why a 180? The lower temp will decrease the efficiency of your engine and drop mpgs. There will be no advantage to having the 180 in a fairly stock NA car, only disadvantages.

Most of the SC'd guys who go 180 is to keep the heat spike down when they get into boost. Because the added compression and heat from the Gen 3 tend to flash cylinder temps quickly.
 
ive been having this problem too, my mechanic flushed it out, no go, so he replaced the radiator and tstat, worked temporarily but the problem came back, hes recommending i get the headers and engine checked for cracks or leaks, he thinks theres a chance its creating an air pocket in the system thats not allowing it to cool down the engine properly. I think i explained that the right way, but either way my car's out now getting the headers checked
 
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