car runs hot with a/c on
#1
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last week i took a 4 hr trip to the beach. i ran the a/c the entire way on the interstate with no problems at all, car hovered around 210 in the middle of the gauge. once we got off the interstate and got into bumper to bumper traffic in 90 degree weather, the car started running hot. so hot it was spewing coolant all over. i filled it back up and went on my way. whenever i turn the a/c on.....the coolant temp gets hotter and hotter. if i dont run a/c the coolant temp is perfectly fine.
sounds to me like the second fan is not comming on when the a/c is turned on, and the condensor is getting very hot and blowing hot air across the radiator. when im cruising at hwy speeds it does not do this, only in slow traffic in hot weather. do yall agree with me on this?
so...which fan is the fan that comes on with the a/c? and where should i check the connections for it? i had my a/c and motor out last summer and eividentally didnt hook that up.
sounds to me like the second fan is not comming on when the a/c is turned on, and the condensor is getting very hot and blowing hot air across the radiator. when im cruising at hwy speeds it does not do this, only in slow traffic in hot weather. do yall agree with me on this?
so...which fan is the fan that comes on with the a/c? and where should i check the connections for it? i had my a/c and motor out last summer and eividentally didnt hook that up.
#2
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take a look at your condenser too... if it has alot of trash and dirt in it that will make it overheat because the fans will not pull air through it like they should... you can try blowing it out with an air hose or spraying it with a water hose
#3
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Its time:
https://ls1tech.com/forums/general-m...bably-why.html
But if your coolant is boiling over...you have another problem. Air in the system. Temps can go all the way into the red and you should not boil over a drop, IF your cooling system is tight. Or, you have 100% water, then just a tiny bit of air will cause it to boil over.
You probably need a new radiator cap, only other way air gets into the system is blown head gaskets.
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https://ls1tech.com/forums/general-m...bably-why.html
But if your coolant is boiling over...you have another problem. Air in the system. Temps can go all the way into the red and you should not boil over a drop, IF your cooling system is tight. Or, you have 100% water, then just a tiny bit of air will cause it to boil over.
You probably need a new radiator cap, only other way air gets into the system is blown head gaskets.
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#5
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very good writeup man. so all that is needed is to clean all the debris and junk off the front of the condensor? i think i may be able to get to most of it with it still in the car actually. ill give this a try tomorrow.
as far as it boiling over....im not sure where the coolant leak was...but when it overheated, i pulled over and collant was running from undernath the car. i let it cool down, filled it up with coolant, checked for the leak and it wasnt doing it anymore. 400 miles later it is still leak free so that was weird. the rad cap is also about a month old so its pretty much brand new. hopefully cleaning this condensor will rid me of the overheating issue!
as far as it boiling over....im not sure where the coolant leak was...but when it overheated, i pulled over and collant was running from undernath the car. i let it cool down, filled it up with coolant, checked for the leak and it wasnt doing it anymore. 400 miles later it is still leak free so that was weird. the rad cap is also about a month old so its pretty much brand new. hopefully cleaning this condensor will rid me of the overheating issue!
#6
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Engines that over heat when the a/c is turned "on", but otherwise always runs cool......is a dirty condensor.
The coolant coming out was probably through the over flow, maybe the tank is full too.
I've yet to here of anyone being able to clean the condensor without at least taking the radiator out to get to the condensor. Spray hoses, air hoses and pressure cleaners haven't worked either. That stuff needs to be physically removed or banged out.
Make sure BOTH fans are coming on together, and that they work on low and high. That can certainly be the problem too.
But people who have 1998-2002 F-Body's......and they've never cleaned their condensors, its the #1 reason they get hot when the a/c is turned on.
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The coolant coming out was probably through the over flow, maybe the tank is full too.
I've yet to here of anyone being able to clean the condensor without at least taking the radiator out to get to the condensor. Spray hoses, air hoses and pressure cleaners haven't worked either. That stuff needs to be physically removed or banged out.
Make sure BOTH fans are coming on together, and that they work on low and high. That can certainly be the problem too.
But people who have 1998-2002 F-Body's......and they've never cleaned their condensors, its the #1 reason they get hot when the a/c is turned on.
.
#7
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LS6427...appreciate the suggestion. i just finished taking the radiator out and cleaning it real good, and got the condensor as clean as possible. the radiator was 5x as dirty as the condensor, which could have still been causing the problems. it was raining out so i couldnt drive it, but i did let the car idle in the driveway for 25 minutes with the a/c on full blast, and the temp never got over 200 the whole time, so i hope its fixed. the tru test will be the bumper to bumper traffic in 90 degree heat!