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99 gp gt overheats when idleing

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Old Dec 15, 2011 | 08:19 AM
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When I change a thermostat I will add coolant into the hole until it'* full, then set the the thermostat in place. No need to bleed then.

Also, have you checked to make sure your radiator fins are clean?
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Old Dec 16, 2011 | 03:56 AM
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Originally Posted by Danthurs
When I change a thermostat I will add coolant into the hole until it'* full, then set the the thermostat in place. No need to bleed then.

Also, have you checked to make sure your radiator fins are clean?
i have not checked my radiator fins but i will. how do i go about cleaning them if they r dirty ((easy cheap way))

im guessing the fins r the millions of thin ittle metal rows on my radiator that the engine breaths threw??

and when u say "add coolant into the little hole" u mean the coolant res? or the coolant overflow tank???

also while checking the car i noticed the cap on the radiator coolant resevoir had a bunch of gunky crud on it from the last car...can that cause any of the issues im haveing?
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Old Dec 16, 2011 | 07:30 AM
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see post #2. as far as the brown chocolate milkshake looking stuff i could tell you what i think that is but i dont want to open that can of worms. theres a bunch of conflicting beliefs on why it does that. you'll have to flush it and change the coolant, i use one of those prestone garden hose adapters and refill with prestone extended life, walmart sells it for cheaper and ive put many 100 thousands of miles on it.
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Old Dec 16, 2011 | 09:55 AM
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Sounds like you need to have your coolant system flushed.

If you have air in the system, there is a bleeder screw on top of the thermostat housing. Back that screw off with the engine up to temperature until you get steam/air/water coming out. Put a rag over it so you don't get burned, and don't back it out too far. Tighten it back up when only water is coming out.

Dan is referring to the small opening you place the thermostat into, inside the thermostat housing. When you replace the thermostat you should fill coolant into that opening until it tops up. If you are not replacing the thermostat, the bleeder screw is the only way to get air out.
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Old Dec 16, 2011 | 11:59 AM
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How does your coolant look? If it'* brown and sludgy, flush it out good. Dex cool is what the car came with. If it was topped off with something other the Dex or a compatible coolant it will sludge up. If your going to use a green coolant, be sure to get all the old coolant out.

Place a light behind the radiator and look threw the vains you should see the light good. If it looks dirty, then spray it with a good degreaser. Then hose it off.
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Old Jan 4, 2012 | 01:04 AM
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Originally Posted by Danthurs
How does your coolant look? If it'* brown and sludgy, flush it out good. Dex cool is what the car came with. If it was topped off with something other the Dex or a compatible coolant it will sludge up. If your going to use a green coolant, be sure to get all the old coolant out.

Place a light behind the radiator and look threw the vains you should see the light good. If it looks dirty, then spray it with a good degreaser. Then hose it off.
I just got back from miami. sorry for the late response...

I turned my car on, let it idle for a while...turned my a/c on and watched my fans for about 10 minutes. after about 15 minutes of changeing the fan velocity they never came on. whats the next move for me. (i never cleaned the radiator finders by the way).
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Old Jan 4, 2012 | 10:38 AM
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Check the fuses for the fans. They should have turned on.
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Old Jan 4, 2012 | 01:03 PM
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You sure your intake isnt leaking? Just throwing that out there because when my intake in my GP let go (3.1) It acted like it was overheating because it was picking up air in the system which cannot flow like a fluid. If air is behind your thermostat it may not open until you give it enough pedal pressure for your water pump to push the air. You know? My gp did the same crap. It would creep all the way up the gauge but it wouldnt be insanely hot. (no steam but overflow would boil)
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Old Jan 5, 2012 | 02:37 AM
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Originally Posted by DanSSEi00
You sure your intake isnt leaking? Just throwing that out there because when my intake in my GP let go (3.1) It acted like it was overheating because it was picking up air in the system which cannot flow like a fluid. If air is behind your thermostat it may not open until you give it enough pedal pressure for your water pump to push the air. You know? My gp did the same crap. It would creep all the way up the gauge but it wouldnt be insanely hot. (no steam but overflow would boil)
im gonna go head and check the relay and the fan switch. YES I DO have an uim leak...but that shouldnt cause it to overheat just at idle...and it shouldnt muck with my fans functionality either. BUT u r right it does move sluggishly and i have noticed it...and i wonderd what the heck it was. thank u
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Old Jan 5, 2012 | 07:56 AM
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A cracked UIM can cause the problems you are seeing, not because coolant is leaking out, but because it is allowing air into the system. The cooling system is closed loop, and does not deal well with air, particularly at idle. Open the bleeder screw on top of the thermostat housing to see if there is air.

How are you determining you engine coolant is running hot at idle? Is it over the operating temperature it should run at, or is it just hotter than when you are driving? I ask because I helped someone with a GP last week who thought his car was running hot at idle, but in fact it was running normal temp at idle, and running cold during normal driving. He saw the temp increase at idle as the issue, when the actual problem was it was running too cold when driving.
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