Car running hot
Thread Starter
Staging Lane
Joined: Aug 2004
Posts: 55
Likes: 0
From: Phoenix, Arizona
Car running hot My T/A (LS1) is running hot all of a sudden. The temp gauge sometimes goes up to 230-235 now as to where it would never get over 210 degrees. It is not boiling over, the air dam is intact, there are no bags or anything covering the radiator, the coolant level is topped off as well. My fans are coming on and now they are staying on even after I turn the key off. That is something that it has never done before even in the summer. Can someone help me trouble shoot what is happening as I am baffled. Thanks, Scott.
I have the exact same problem with mine. Your fans should come on at 210°F. However, they do not (for whatever reason). They will turn on at 230°F but that is because it goes into thermal protection mode. I've had the problem for a couple of years and haven't spent enough time figuring it out. If you turn the A/C on(fans run with A/C on), you shouldn't pass 210°F (right?). Also, if your driving over 40mph, it'll run cooler (right?). This is annoying as hell and I am also looking for the answer. I am thinking maybe a thermal sending unit that goes to the PCM. But I don't know if one exists or where it is.
Also, make sure you check the basics.... fluid level, proper air bleeding from system, fan operation, thermostat.
If I figure mine out, I'll definately let you know.
Also, make sure you check the basics.... fluid level, proper air bleeding from system, fan operation, thermostat.
If I figure mine out, I'll definately let you know.
Thread Starter
Staging Lane
Joined: Aug 2004
Posts: 55
Likes: 0
From: Phoenix, Arizona
Originally Posted by tattooZ
Thermostat.
Originally Posted by QuickSilver T/A
My T/A (LS1) is running hot all of a sudden. The temp gauge sometimes goes up to 230-235 now as to where it would never get over 210 degrees. It is not boiling over, the air dam is intact, there are no bags or anything covering the radiator, the coolant level is topped off as well. My fans are coming on and now they are staying on even after I turn the key off. That is something that it has never done before even in the summer. Can someone help me trouble shoot what is happening as I am baffled. Thanks, Scott.
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On The Tree
Joined: Aug 2002
Posts: 150
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From: Vacaville, CA
His fans ARE coming on normally. The temp reading on those guages is nothing more than an idiot guage. It is the thermostat to blame. He stated that he is not boiling over, his fans come on, fluid topped off.
Change your thermostat, and you will fix your car.
Change your thermostat, and you will fix your car.
Originally Posted by jkichline
What does the thermostat have to do with the fans coming on late? 
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Originally Posted by tattooZ
His fans ARE coming on normally. The temp reading on those guages is nothing more than an idiot guage. It is the thermostat to blame. He stated that he is not boiling over, his fans come on, fluid topped off.
Change your thermostat, and you will fix your car.
Change your thermostat, and you will fix your car.
(or find the receipt 
) which thermostat I put in (160° or 180°). I believe that if I used a 160° stat, that may also cause this problem. I plan on putting in a 180° within a couple weeks. I'll let you know how I make out.I'm not sure I agree with the "idiot gauge" comment.
In my experience, those temp gauges aren't as far off as most people think. If the gauge is off, the usual culprit is the sending unit. Does the sending unit go to the gauge AND the PCM? or are there separate ones?
Originally Posted by QuickSilver T/A
Please explain this to me. The car does NOT boilover and I was under the impression that thermostats basically work, or they dont? A tell tale sign of a bad thermostat is usually when it boils over correct?
Thread Starter
Staging Lane
Joined: Aug 2004
Posts: 55
Likes: 0
From: Phoenix, Arizona
***UPDATE***
I replaced the thermostat and it did not fix my problem at all. I was doubting it being the thermostat but figured I would give it a try anyway and follow the consensus of advice. The worst that would happen is that I would solve the problem and end up with a new thermostat.
So I took it to my main wrench and he fixed the problem. It ended up being that the radiator was clogged. He flushed my entire system of Dexcool and went with the traditional Glycol green. He ordered me a new radiator and removed and replaced the old one. The old radiator was completely drained and weighed at least 30 lbs more than the new radiator because it was clogged and corroded so badly. My mechanic had tons of bad comments about this Dexcool crap and what it does to the cooling system.
My car was owned by an attorney and was regularly maintained by the dealer so please no comments that the Dexcool was never changed, flushed, or maintained. Anyways I just wanted to tell my tale so that it may help someone else and to thank the people who tried to help me. Thanks, Scott.
I replaced the thermostat and it did not fix my problem at all. I was doubting it being the thermostat but figured I would give it a try anyway and follow the consensus of advice. The worst that would happen is that I would solve the problem and end up with a new thermostat.
So I took it to my main wrench and he fixed the problem. It ended up being that the radiator was clogged. He flushed my entire system of Dexcool and went with the traditional Glycol green. He ordered me a new radiator and removed and replaced the old one. The old radiator was completely drained and weighed at least 30 lbs more than the new radiator because it was clogged and corroded so badly. My mechanic had tons of bad comments about this Dexcool crap and what it does to the cooling system.
My car was owned by an attorney and was regularly maintained by the dealer so please no comments that the Dexcool was never changed, flushed, or maintained. Anyways I just wanted to tell my tale so that it may help someone else and to thank the people who tried to help me. Thanks, Scott.
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From: Live Oak, FL - in the woods where the creatures lurk.
30 lbs more! Holy smokes.
That is weird. I've drained and flushed mine several
times, have had no problems on my high mileage
car.
This last time I did change coolant type, went with the
extended life coolant from Advance that is
compatible with all coolant types.
I also use distilled water when I do the mix.
That is weird. I've drained and flushed mine several
times, have had no problems on my high mileage
car.
This last time I did change coolant type, went with the
extended life coolant from Advance that is
compatible with all coolant types.
I also use distilled water when I do the mix.
Its good that you got it fixed but your mechanic shouldnt have put the green stuff in there, i guess if he got it ALL out of the block then it will still work but its suppose to be harmful to the aluminum, also if the 2 are mixed Dexacool and Green it forms a kind of sludge which will definatly clog up some stuff. I dont have a clue as to why your radiator was so clogged, but you said it was getting hot 'all of a sudden' you didnt happen to top it off w/green coolent did you? It seems strange that it would just randomly get clogged so bad, im curious where this 30lbs came from,lol. before i changed mine out it has 120k on it and the same fluid and it wasnt clogged badly
Originally Posted by jkichline
Not necessarily. They can become sticky or not open and close all the way. You could also have the wrong thermostat. I would double check this but I believe that the LT-1 takes a 180° stat and the LS-1 takes a 195° stat.
Originally Posted by 98NBM_TransAm
I'd have your car hooked up to a tuner and see what the fans are programmed to come on at, i had that problem in the summer and lowerd my fan temps some and it went away, you might also want to check your fan relay's and loop them w/a paperclip w/the car off to see if they come on, if they do try replacing the relay(s) and see where your at (this being before you pay someone to mess w/your fan temps, unless you can get it done for free or dont mind paying)