Issue With Coolant Temp Running High When Driving
Thread Starter
Intermediate
Joined: Jul 2012
Posts: 25
Likes: 4
Issue With Coolant Temp Running High When Driving
Having issues with the coolant temps running around 230-235 with 240ish being the highest it has gotten. It was worse prior the replacements that were made to the car.
Already replaced the water pump, coolant tank, radiator and cleaned out the much of the debris in the fin area. Hoses are good, no cracks or leaks when the mechanic checked.
Fans are turning on with no issues. I have a 160 degree thermostat that was changed around a year ago.
Running dex cool on it as well.
My mechanic thinks it could be a head gasket issue.
I searched on here for solutions, but the only thing I didn't do was bleed the air which I will do this week.
Just stumped on what else could be the issue.
Already replaced the water pump, coolant tank, radiator and cleaned out the much of the debris in the fin area. Hoses are good, no cracks or leaks when the mechanic checked.
Fans are turning on with no issues. I have a 160 degree thermostat that was changed around a year ago.
Running dex cool on it as well.
My mechanic thinks it could be a head gasket issue.
I searched on here for solutions, but the only thing I didn't do was bleed the air which I will do this week.
Just stumped on what else could be the issue.
.
Joined: Apr 2013
Posts: 5,042
Likes: 1,156
From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
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Joined: Apr 2013
Posts: 5,042
Likes: 1,156
From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
Having issues with the coolant temps running around 230-235 with 240ish being the highest it has gotten. It was worse prior the replacements that were made to the car.
Already replaced the water pump, coolant tank, radiator and cleaned out the much of the debris in the fin area. Hoses are good, no cracks or leaks when the mechanic checked.
Fans are turning on with no issues. I have a 160 degree thermostat that was changed around a year ago.
Running dex cool on it as well.
My mechanic thinks it could be a head gasket issue.
I searched on here for solutions, but the only thing I didn't do was bleed the air which I will do this week.
Just stumped on what else could be the issue.
Already replaced the water pump, coolant tank, radiator and cleaned out the much of the debris in the fin area. Hoses are good, no cracks or leaks when the mechanic checked.
Fans are turning on with no issues. I have a 160 degree thermostat that was changed around a year ago.
Running dex cool on it as well.
My mechanic thinks it could be a head gasket issue.
I searched on here for solutions, but the only thing I didn't do was bleed the air which I will do this week.
Just stumped on what else could be the issue.
Thread Starter
Intermediate
Joined: Jul 2012
Posts: 25
Likes: 4
I only noticed that after the water pump was installed. I couldn't see any leaks nor was it a malfunctioning part that the shop got for it.
But I doubt something like the cooling issue would be anything with head gaskets?
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Joined: May 2008
Posts: 174
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From: Pahrump NV.
Having issues with the coolant temps running around 230-235 with 240ish being the highest it has gotten. It was worse prior the replacements that were made to the car.
Already replaced the water pump, coolant tank, radiator and cleaned out the much of the debris in the fin area. Hoses are good, no cracks or leaks when the mechanic checked.
Fans are turning on with no issues. I have a 160 degree thermostat that was changed around a year ago.
Running dex cool on it as well.
My mechanic thinks it could be a head gasket issue.
I searched on here for solutions, but the only thing I didn't do was bleed the air which I will do this week.
Just stumped on what else could be the issue.
Already replaced the water pump, coolant tank, radiator and cleaned out the much of the debris in the fin area. Hoses are good, no cracks or leaks when the mechanic checked.
Fans are turning on with no issues. I have a 160 degree thermostat that was changed around a year ago.
Running dex cool on it as well.
My mechanic thinks it could be a head gasket issue.
I searched on here for solutions, but the only thing I didn't do was bleed the air which I will do this week.
Just stumped on what else could be the issue.
220 - 230 is normal for cruising in city traffic on a warm day. Fans are factory set to turn on at 220-230 unless reprogrammed by a tuner.
Mine runs 190-200 on hiway even in 120 day jumping to 230-240 in heavy bumper to bumper traffic on a warm 120 degree day.
Air in system could very well be issue, But would expect over heating if it was indeed caused by Air in the heads.
A better possible issue is the Fan relay! mine was bad only staying on in single speed after replacing relay I had dual speed fans working stayed cooler on warm days in traffic.around 220 solid.
I Live in Death Valley
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
Fans are turned off at 35mph by the PCM, you're car's highway temperatures are higher then normal. Does your car have the center air dam in place, if it does then I would recommend performing the the FSM procedure for burping the cooling system.
Race Director
Joined: Oct 2004
Posts: 12,864
Likes: 4,667
Ya, that is the thing. My temps before I noticed was hovering around 220 driving freeway or cruising. It would rarely if ever get beyond that.
I only noticed that after the water pump was installed. I couldn't see any leaks nor was it a malfunctioning part that the shop got for it.
Going to try that and see.
Interesting, I would have to have that checked by the shop and see.
But I doubt something like the cooling issue would be anything with head gaskets?
I only noticed that after the water pump was installed. I couldn't see any leaks nor was it a malfunctioning part that the shop got for it.
Going to try that and see.
Interesting, I would have to have that checked by the shop and see.
But I doubt something like the cooling issue would be anything with head gaskets?
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
A leaking head gasket will cause air bubbles in the coolant, you can remove the coolant tank pressure cap and check for bubbles, you can also rent or buy a coolant system pressure tester.
Uneducated autodidact
Joined: Feb 2001
Posts: 5,413
Likes: 252
From: West of the Sabine, Texas
. If you pull over and idle and it cools down that could be the problem. The thermostat opening temperature controls how cold the coolant gets, not how hot.
Thread Starter
Intermediate
Joined: Jul 2012
Posts: 25
Likes: 4
160 Thermostat is too cold for a LS engine!, Aluminum engine needs heat 190 thermostat is what I run. Never run colder than what mfg suggests! Heat is Power!
220 - 230 is normal for cruising in city traffic on a warm day. Fans are factory set to turn on at 220-230 unless reprogrammed by a tuner.
Mine runs 190-200 on hiway even in 120 day jumping to 230-240 in heavy bumper to bumper traffic on a warm 120 degree day.
Air in system could very well be issue, But would expect over heating if it was indeed caused by Air in the heads.
A better possible issue is the Fan relay! mine was bad only staying on in single speed after replacing relay I had dual speed fans working stayed cooler on warm days in traffic.around 220 solid.
I Live in Death Valley
220 - 230 is normal for cruising in city traffic on a warm day. Fans are factory set to turn on at 220-230 unless reprogrammed by a tuner.
Mine runs 190-200 on hiway even in 120 day jumping to 230-240 in heavy bumper to bumper traffic on a warm 120 degree day.
Air in system could very well be issue, But would expect over heating if it was indeed caused by Air in the heads.
A better possible issue is the Fan relay! mine was bad only staying on in single speed after replacing relay I had dual speed fans working stayed cooler on warm days in traffic.around 220 solid.
I Live in Death Valley
More and more it is starting to look like it would be a gasket issue.
Le Mans Master
Joined: Feb 2021
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From: Florida
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Uh, a leaking head gasket can, and will, increase coolant temps dramatically. If they're large enough, they will overwhelm any cooling system. Think about it like this; with a bad gasket, it's exposing the coolant to the combustion chamber temperatures, which are over 1,000°F!!! Similar to heating the coolant with a blowtorch every time the cylinder(s) fire!!!
Le Mans Master
Joined: Feb 2021
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From: Florida
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There’s only two components in play, circulation and air flow.
You have changed all of the circulation components and cleaned the radiator fins.
I am curious about the thermostat. Did you change that before or after it was running hot. Also, the history. For example, was it running 200° normally and then all the sudden one day it started running hot?
You have changed all of the circulation components and cleaned the radiator fins.
I am curious about the thermostat. Did you change that before or after it was running hot. Also, the history. For example, was it running 200° normally and then all the sudden one day it started running hot?
Drifting
Joined: Sep 2022
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From: In the woods
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My 2K used to run real hot when I got it, up to 240 in traffic very quickly. The air dam was missing and the radiator/condenser were covered with debris of all sorts. Replacing the dam and cleaning the rad/cond now has it running 195/200 cruising and while it does go up to 230 or so when stuck in traffic as soon as I am moving again it drops right back down.