Bad Coolant Temp sensor?
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Joined: Mar 2015
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From: oceanside california
Bad Coolant Temp sensor?
Hello firstly off i have a 2006 c6 stock red vette, and here recently sort of suddenly i would occasionally look to the left gauge and see my engine temperature be abnormally high like 230 or 240 and this happened in stop and go traffic so i didnt think too much about it. After traffic broke loose it was normal temps.Then today i left my car on and ran inside and came outside and a "CHECK COOLANT LEVELS" message came up and the temperature was at like 235+......
So i let the car sit and checked my coolant levels and it wasn't that low at all but i refilled the coolant to where it should be and then burped the car. Then next day i drove it around and then the temperature started climbing really high again like 240+ going at like 30mph. So everytime it got that high i would pull over and wait. BUT a tricky thing is after i wait 30seconds i turn the car on to look at the temperature dial and display and it says 200 (normal temp for my car)
how in the hell did it go from 240 to 200 in less than a minute after turning it off?
also.... no leaks or loose lines i checked. maybe still air in the lines?
So i let the car sit and checked my coolant levels and it wasn't that low at all but i refilled the coolant to where it should be and then burped the car. Then next day i drove it around and then the temperature started climbing really high again like 240+ going at like 30mph. So everytime it got that high i would pull over and wait. BUT a tricky thing is after i wait 30seconds i turn the car on to look at the temperature dial and display and it says 200 (normal temp for my car)
how in the hell did it go from 240 to 200 in less than a minute after turning it off?
also.... no leaks or loose lines i checked. maybe still air in the lines?
Melting Slicks
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From: Bridgewater New Jersey
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From: oceanside california
Melting Slicks
Joined: Dec 2013
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From: Bridgewater New Jersey
If there is positively no air in the system, it possible that the coolant sensor is going bad.
Less likely a water pump but that's not a fore sure thing also.
The sensor is cheap enough to get replaced, but I would definitively get one from the car dealer, as some off brands of electronics are sometimes problematic.
How many miles are on the car?
Less likely a water pump but that's not a fore sure thing also.
The sensor is cheap enough to get replaced, but I would definitively get one from the car dealer, as some off brands of electronics are sometimes problematic.
How many miles are on the car?
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Joined: Mar 2015
Posts: 57
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From: oceanside california
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Thread Starter
Advanced
Joined: Mar 2015
Posts: 57
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From: oceanside california
If there is positively no air in the system, it possible that the coolant sensor is going bad.
Less likely a water pump but that's not a fore sure thing also.
The sensor is cheap enough to get replaced, but I would definitively get one from the car dealer, as some off brands of electronics are sometimes problematic.
How many miles are on the car?
Less likely a water pump but that's not a fore sure thing also.
The sensor is cheap enough to get replaced, but I would definitively get one from the car dealer, as some off brands of electronics are sometimes problematic.
How many miles are on the car?
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Joined: Mar 2015
Posts: 57
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From: oceanside california
yeah my coolant color is clear and bright green from "Peak" coolant how would i know if their's a clog
Melting Slicks
Joined: Dec 2013
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From: Bridgewater New Jersey
Melting Slicks
Joined: Dec 2013
Posts: 2,232
Likes: 315
From: Bridgewater New Jersey
Using a Laser Infrared Temperature Gun, while the engine is running, it could be used to check the temps at each core row, as a blockage would be indicated by a lower temp than a core right next to it. I would think this to be tricky to do since there not much cores very visible. Other than that, a specialty radiator shop could help you out there. I think a clog is a very long shot here, since you stated the fluid is clear and brightly colored.
Thread Starter
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Joined: Mar 2015
Posts: 57
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From: oceanside california
Using a Laser Infrared Temperature Gun, while the engine is running, it could be used to check the temps at each core row, as a blockage would be indicated by a lower temp than a core right next to it. I would think this to be tricky to do since there not much cores very visible. Other than that, a specialty radiator shop could help you out there. I think a clog is a very long shot here, since you stated the fluid is clear and brightly colored.
Melting Slicks
Joined: Dec 2013
Posts: 2,232
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From: Bridgewater New Jersey
I have always just ran the engine at idle until I feel that the thermostat has opened and added coolant slowly keeping the coolant tank cap off, watching for bubbles to come up. Once I see no more bubbles I would setup a fast idle so that coolant would get drawn from the tank for a few minutes, then close it up.
Race Director
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So your going to need to have a professional flush to get the sludge out of the system.
Hence something like super flushes to start with with the T stat removed, then distilled water flushes to get the last of the super flush out, then T stat replaced with a new one and the system refilled once clean with 50/50 Dex-cool.
And since the old mixed radiator fluids and flushing agent need to be reclaimed, this is not a project to just do out in drive way.
Last edited by Dano523; Jun 16, 2016 at 09:33 PM.