Thread: 2008 grand prix runs hot

I just started using the air conditioner for the first time this season and I am noticing that my car tends to run hot. The gauge never gets in the red but gets up to the line before it. Is this normal for this model car? I have recently had the water pump replaced and had issues with my heat so I have had the heater core flushed on two seperate occasions as well. Could this be a symptom of a faulty thermostat? I checked the overflow resovoir for the antifreeze and it appeared to be normal.I should mention that this only happens when idling in traffic. As soon as I start driving the fans kick in and the gauge goes down but then immediately go back up as soon as Im stopped. Just wanted to bounce this off you guys.
John

Back again. I was stuck in traffic this morning and I noticed the gauge creeping up towards the red again. I put on the ac and it went back down but at that very moment traffic let up as well so I dont know if putting the ac on fixed it or if it was that I was able to go faster. Anyway, since I last posted, I changed the thermostat and had air taken out of the system as well as had my radiator flushed. It seemed to run cooler this past month but today started to run hot again. Any ideas? My engine light hasnt gone on so I cant check for codes. Im at a loss. Outside temp was only around 60 degrees F.

They kick on so I know they work but I feel like maybe they arent kicking on soon enough. I dont know what else to do. Over the winter when I had my heater core cleaned out (I had problems with there being no heat) the mechanic told me that I might start having problems with "corrosion" or overheating issues. Can cleaning out the heater core be the cause of this?

I brought my car into a local shop and he said that the reason my car is running so hot is because air is getting into the heads (??) and its needs new head gaskets and it also needs the valves and the heads resurfaced. The cost he gave me was $1750. Totally wasnt expecting that! Does this sound plausible? I certainly dont want to spend this kind of money if its a sham. Plus its going to take about a week to do the job. I should also mention that its not blowing smoke of any kind besides the normal exhaust which I always thought was one of the reasons to have this kind of work done.

Thats the thing. I dont have any leaks nor do I smell anything sweet like the smell of antifreeze. Hard to tell if the guy just wants to make a quick buck.

I have 172,000 miles on it. I work in a high school and they teach auto there so the auto teacher was the one who drained the coolant about a month ago. The prcoess he used was connecting a hose to some kit I bought at the auto parts store. He said that there was a ton of gunk in there which I am assuming was the dex cool.

I dont think so

I went through a the same struggle with mine. Im almost certain it will be your issue too. I solved mine by replacing the radiator. I wish I would have taken it apart first and looked at the old one it was really gunked up and not letting air flow through with only 100k on it. You cant get it clean enough while its installed in the car the AC blocks you from power washing it. Take out the radiator and power wash the fins, Id bet its your problem

Head gaskets are rare failures on the 3800. It can run hot for a lot of miles. Just keep it full of coolant.

My 2000 GP was ran without coolant (blew the drain plug out) and overheated. The shop said it had bad head gasket and needed new engine. 3300 bucks. I laughed and put a new drain plug in, filled with coolant and it ran another 30000 miles before it finally gave up the ghost at 330 K.


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So should I get a second opinion on this or are you saying its just the radiator that needs to be replaced?