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Over heating on stock engine with AC on?

Old 06-23-2017, 03:51 PM
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Over heating on stock engine with AC on?

Hey all, been reading a lot on here. My car will over heat on highway or high speeds with AC on. It's been over 100 out so that Ac struggles regardless. The motor got up past half to about 230. Not sure what is too hot for these cars. Never went past that. Pulled over and coolant was bubbling. My fan is wired always on with ignition on. Single fan. Engine also has a trans cooler. As soon as I turn AC off the car cools back down.

Stock radiator
air damn in place
car will cool when I come to a stop or in town speeds when the fan can do it's job
i added water wetter and it helped significantly but still a little past half
recently replaced wp radiator and hoses

ive also cleaned the radiator and condensor to remove dirt.

Any idea? Love my Ac but don't want to cook the engine on the highway
Old 06-23-2017, 05:25 PM
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Re: Over heating on stock engine with AC on?

Does your car have the plastic air dam under the radiator?
Old 06-23-2017, 05:28 PM
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Re: Over heating on stock engine with AC on?

Originally Posted by five7kid
Does your car have the plastic air dam under the radiator?
yup even fixed sagging ground effects
Old 06-23-2017, 07:16 PM
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Re: Over heating on stock engine with AC on?

Im having this same exact issue with my ls swap setup and a/c. Im even running ls1 fans and a 160 stat. Car runs perfectly normal temp with no a/c or in trafffic with a/c. Once on the highway it creeps up to 230 and stays there. Turn off the a/c, or hit traffic and it drops. I even picked up a whole factory airdam setup, and it helped. Before the airdam the temp would continue to rise above 230.

My next step will be a larger radiator, then maybe some aftermarket fans 😕
Old 06-23-2017, 09:07 PM
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Re: Over heating on stock engine with AC on?

Originally Posted by mgg4591
Im having this same exact issue with my ls swap setup and a/c. Im even running ls1 fans and a 160 stat. Car runs perfectly normal temp with no a/c or in trafffic with a/c. Once on the highway it creeps up to 230 and stays there. Turn off the a/c, or hit traffic and it drops. I even picked up a whole factory airdam setup, and it helped. Before the airdam the temp would continue to rise above 230.

My next step will be a larger radiator, then maybe some aftermarket fans 😕
same I have the 195 degree thermostat however. I'm beginning to think they just can't handle the heat and Ac combined just not built for it unless I plan on upgrading the radiator
Old 06-24-2017, 12:10 PM
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Re: Over heating on stock engine with AC on?

Check that the fan is blowing into the engine compartment. Reverse the wiring and the fan will blow air out of the front of the car. That works at low speed, but not on the highway.

RBob.
Old 06-24-2017, 02:11 PM
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Re: Over heating on stock engine with AC on?

Originally Posted by RBob
Check that the fan is blowing into the engine compartment. Reverse the wiring and the fan will blow air out of the front of the car. That works at low speed, but not on the highway.

RBob.
thats a good idea let me check
Old 06-24-2017, 06:33 PM
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Re: Over heating on stock engine with AC on?

Today's weather was 75-80 and cool. Car didn't run hot at all. Didn't even get to half and Ac worked perfectly. Going to just assume it won't be a good summer highway car until I switch to a better radiator


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