weird overheating issue?
Thread Starter
Teching In
Joined: Aug 2013
Posts: 33
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From: TN
weird overheating issue? Hey guys, i havent really dug into this issue simply because of the fact that i have a DD, and my camaro just sits, but anyways.
My car will slowly overheat if i go over 60 mph for an extended period of time, not 59 mph, but exactly 60. weird right?? i could drive on the interstate going 75 mph, and like five min. later it will start to slowly rise. i can slow down to sixty or below and it will cool back down slowly. i can drive around town for hours and it wont overheat. but interstate or extended hwy is a different story. thanks guys.
Chaz
My car will slowly overheat if i go over 60 mph for an extended period of time, not 59 mph, but exactly 60. weird right?? i could drive on the interstate going 75 mph, and like five min. later it will start to slowly rise. i can slow down to sixty or below and it will cool back down slowly. i can drive around town for hours and it wont overheat. but interstate or extended hwy is a different story. thanks guys.
Chaz
Teching In
Joined: Mar 2012
Posts: 42
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Hmm, that is weird. Have you had an opportunity to verify that both of your fans are still commanding on at that speed? say if that 75mph wind resistance was tugging a loose whether protector or something, and that the plug to a fan or related component was being physically moved, it would be good to verify your fan commands are working I would think. As you probably know the "normal" circumstance would be that you would overheat in town due to reduced airflow then cool down at higher speed
TECH Addict
Joined: Dec 2010
Posts: 2,610
Likes: 4
From: Maricopa, AZ
weird overheating issue? Usually a high speed cooling issue is coolant flow related. But as stated above, rarely an air flow problem can cause it.
The cooling fans should turn off at 36mph (unless the car is way overheating) according the the stock tune. At 36 MPH the air flow through the radiator matches what the fans can pull through it anyway. Above 36mph the fans being on can reduce air flow (albeit not enough to cause cooling issues, but they are not needed and will only increase engine load via the alternator and reduce fuel economy).
OP, next time you are at say 55MPH select a lower gear and get the RPMS up just a tad (like the same rpm you would be in at 75 or so in high gear). If the condition repeats, look into a coolant flow problem. If not look into an airflow problem.
Is the air dam installed and not damaged? Are the ducts and plastics parts in front of the radiator secured so the wind doesn't blow them on to the condensor?
The cooling fans should turn off at 36mph (unless the car is way overheating) according the the stock tune. At 36 MPH the air flow through the radiator matches what the fans can pull through it anyway. Above 36mph the fans being on can reduce air flow (albeit not enough to cause cooling issues, but they are not needed and will only increase engine load via the alternator and reduce fuel economy).
OP, next time you are at say 55MPH select a lower gear and get the RPMS up just a tad (like the same rpm you would be in at 75 or so in high gear). If the condition repeats, look into a coolant flow problem. If not look into an airflow problem.
Is the air dam installed and not damaged? Are the ducts and plastics parts in front of the radiator secured so the wind doesn't blow them on to the condensor?
With these cars, more times than not it has to do with the condition of the air dam. The air flow for the radiator is from underneath the car via air dam. If it is missing or damaged air will be diverted away from the radiator causing exactly what you're seeing.
