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Car Running Hot.. Need help

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Old Sep 8, 2009 | 08:22 PM
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Default Car Running Hot.. Need help

The last two days I have noticed that the car has been going over the 210 mark, up to about 230. It will do this under constant rpm's. If I keep my foot on the gas it keeps climbing. Once I get off the throttle, the temp slowly goes down. This usually happens when I am riding on the freeway or when I push it on the street for a good amount of time, then I can hear the fans at full speed. It is weird because it has never gotten hot on the freeway nor at night.

Things that I have checked:
- Both fans come on a little over the 210 mark.
- Radiator is clear of any bags/garbage.
- Coolant reservoir is full.
- Radiator is full of coolant.
- Plastic thing under the car that sends air up to radiator is still there.

Any help would be appreciated, thanks..
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Old Sep 8, 2009 | 08:49 PM
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Might have a bad t-stat. If all else is ok and fluids are topped off, thats a good possibility.

Take it out and toss it in a pot of water with a hand held cooking thermometer. Hold the thermometer right next to the t-stat as the water gets hotter and hotter. See if it opens up when its supposed to.

.
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Old Sep 8, 2009 | 10:52 PM
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All that I could think of would be a bad t-stat. What is the temp of the stock one?
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Old Sep 8, 2009 | 10:54 PM
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Originally Posted by THE PUNSSHR
All that I could think of would be a bad t-stat. What is the temp of the stock one?
I think the stock ones are 195*...not positive.

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Old Sep 9, 2009 | 07:50 AM
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Make sure you don't have a bunch of junk on the surface of your radiator. If air can't move over the fins, the system won't cool efficiently when you add load to the system.
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Old Sep 9, 2009 | 10:22 AM
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if it isn't junk on the radiator blocking airflow, then it is most likely a stuck thermostat.
What typically happens is the thermostat freezes in the open position where it normally sits when the engine is hot under a normal to light load, which is fine until the engine goes under heavier load and the thermostat can't open further.
I assume it's a 2002 f-body or earlier, which is now at least 7 years old, if the coolant hasn't been refreshed now would be a good time to do it; worse case is the radiator is gunked up from the antifreeze going bad causing the overheat.
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Old Sep 9, 2009 | 07:25 PM
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Nothing is blocking the airflow to the radiator, I will have to change out the thermostat and flush out the coolant system. Should I just go with a stock t-stat or any other choices?
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Old Sep 9, 2009 | 07:42 PM
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I recommend a 160 deg thermosat.
reprogram the fans to come on earlier.
Don't forget you will need to burp the system
to remove any air pockets.
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Old Sep 9, 2009 | 07:46 PM
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Would I be able to gat a 160deg t-stat at the local auto parts store? Im trying to get this fix asap..
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Old Sep 9, 2009 | 08:09 PM
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Originally Posted by THE PUNSSHR
Would I be able to gat a 160deg t-stat at the local auto parts store? Im trying to get this fix asap..
If you get the 160 and you DON'T also get the PCM programmed so the fans come on earlier, like at 190*, you will have a potnetially worse overheating situation.

WITHOUT programming:
Highway cruising, you should be fine.
City driving in traffic...you'll overheat pretty quick.
.
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Old Sep 9, 2009 | 08:15 PM
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So a stock one if I don't want to program the PCM, and 160 and program PCM?
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Old Sep 9, 2009 | 08:29 PM
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Originally Posted by the punsshr
so a stock one if i don't want to program the pcm, and 160 and program pcm?


.
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Old Sep 10, 2009 | 07:03 AM
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Given that you live in California, I'd suggest that you look at what a new thermostat spec will do to your emissions before considering a switch.
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Old Sep 10, 2009 | 12:49 PM
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Originally Posted by LS6427
If you get the 160 and you DON'T also get the PCM programmed so the fans come on earlier, like at 190*, you will have a potnetially worse overheating situation.

WITHOUT programming:
Highway cruising, you should be fine.
City driving in traffic...you'll overheat pretty quick.
.
No you won't....But is BEST to get the fans reprogrammed to TAKE ADVANTAGE of the earlier opening t-stat
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Old Sep 10, 2009 | 01:15 PM
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Originally Posted by SOMbitch
No you won't....But is BEST to get the fans reprogrammed to TAKE ADVANTAGE of the earlier opening t-stat
Yes you can, because the thermostat at 160 will no longer properly control coolant flow with normal fan set. It just goes to full open and stays there. The end result in a really hot climate is the engine overheats, and you may not know it, because the coolant isn't in contact with the hot parts long enough to remove the heat. Coolant reads 160, engine is actually burning up.
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