Coolant temperature question
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From: New England
Coolant temperature question
My 2004 has had a 160 degree thermostat and reprogrammed fans for about 5 years. Today the outside temp was only about 84. Wondering how/why the coolant temp could get up to 220 even with a 160 thermostat?
I'm NOT worried about that temp in general. Just curious what might have changed. Normally it wouldn't go over 190.
I don't want to make this a debate about 160/180 thermostats. Thanks
I'm NOT worried about that temp in general. Just curious what might have changed. Normally it wouldn't go over 190.
I don't want to make this a debate about 160/180 thermostats. Thanks
Burning Brakes
Joined: May 2013
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From: Lynn MA
I don't have an answer for you but a possible solution. I swear by water wetter by Redline. I was having issues in warm to hot weather with higher than normal temps. Did some research and found it to be a good option. Well bought a 12 oz bottle and added it and it knocked the temp down about 20 degrees. Worked so well I put a bottle in my 2005 supercharged GTO and got the same results. It's something you can try and it won't hurt anything and it's just $10.00
Burning Brakes
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From: Philo IL
A thermostat that is stuck closed will also cause temps to go up. Can't cool water that doesn't circulate. Also, check to be sure that the fans are operating. Could be possible that one of the motors pooped, wiring has been damaged somehow, or maybe even a bad fuse or relay could keep them from turning on. Just some ideas on things to check.
Last edited by oneandgone; Jul 1, 2017 at 06:55 PM.
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The 160 thermostat is just the opening temp to provide water circulation and it DOES NOT guarantee that the coolant temp will stay below a set value. That job is left to the correct operation of the cooling system including getting adequate air flow through the radiator fins.
I would start by getting the car up in the air and insuring that the cooling fins are clear of debris so that air can flow in order to be able to cool the water in the radiator. Bet there is plenty of junk against the fins preventing air flow. Perhaps even a plastic bag or two that got sucked in as the C5 is a bottom feeder for radiator cooling air........
I would start by getting the car up in the air and insuring that the cooling fins are clear of debris so that air can flow in order to be able to cool the water in the radiator. Bet there is plenty of junk against the fins preventing air flow. Perhaps even a plastic bag or two that got sucked in as the C5 is a bottom feeder for radiator cooling air........
you are right on the money 
The thermostat only dictates the temp at which it opens. After that it's up to the quality and condition of your entire system to keep it cool.
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if it has been running 190 consistently for the past 5 years and now suddenly went up to 220 I agree with starting at the radiator fins and making sure they are clean... also check the coolant level and check for any small leaks if the coolant level is low and might as well make sure both fans are operating... I had a similar issue a couple of years ago where one of my fans quit working and caused my temps to go up to around 230 and usually it sits in the high 190's to 200
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The 160 thermostat is just the opening temp to provide water circulation and it DOES NOT guarantee that the coolant temp will stay below a set value. That job is left to the correct operation of the cooling system including getting adequate air flow through the radiator fins.
I would start by getting the car up in the air and insuring that the cooling fins are clear of debris so that air can flow in order to be able to cool the water in the radiator. Bet there is plenty of junk against the fins preventing air flow. Perhaps even a plastic bag or two that got sucked in as the C5 is a bottom feeder for radiator cooling air........
I would start by getting the car up in the air and insuring that the cooling fins are clear of debris so that air can flow in order to be able to cool the water in the radiator. Bet there is plenty of junk against the fins preventing air flow. Perhaps even a plastic bag or two that got sucked in as the C5 is a bottom feeder for radiator cooling air........
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If with the 160 thermo it ran cool then now it begins to run like 190 with normal temps can point to a few things
1 your thermo is NOT working properly anymore either stuck open or slightly closed
2 your fans are NOT coming on
3 your radiator fins are clogged with debris
4 Your coolant is OLD
5 If your car s an automatic you have to remember that the trans fluid is cooled by your radiator-----IF your trans is running HOT it will in turn make your coolant temps HOT as well---Try changing your trans fluid old fluid will run hotter--- inspect the trans filter--
1 your thermo is NOT working properly anymore either stuck open or slightly closed
2 your fans are NOT coming on
3 your radiator fins are clogged with debris
4 Your coolant is OLD
5 If your car s an automatic you have to remember that the trans fluid is cooled by your radiator-----IF your trans is running HOT it will in turn make your coolant temps HOT as well---Try changing your trans fluid old fluid will run hotter--- inspect the trans filter--
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From: Buffalo Texas
The 160 thermostat is just the opening temp to provide water circulation and it DOES NOT guarantee that the coolant temp will stay below a set value. That job is left to the correct operation of the cooling system including getting adequate air flow through the radiator fins.
I would start by getting the car up in the air and insuring that the cooling fins are clear of debris so that air can flow in order to be able to cool the water in the radiator. Bet there is plenty of junk against the fins preventing air flow. Perhaps even a plastic bag or two that got sucked in as the C5 is a bottom feeder for radiator cooling air........
I would start by getting the car up in the air and insuring that the cooling fins are clear of debris so that air can flow in order to be able to cool the water in the radiator. Bet there is plenty of junk against the fins preventing air flow. Perhaps even a plastic bag or two that got sucked in as the C5 is a bottom feeder for radiator cooling air........
Le Mans Master
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From: Ft. Lauderdale Fl
Put a jacking puck under and jack up a side (you choose which side) and take a look. I had a T-shirt wrapped around the left fan.....it took out the fan, the fuse and the relay. Do an inspection...it will take five minutes if you put down the beer.
Sorry, to post on yesterdays story, was out of the country for the past two weeks. JFK on the 4th of July was something else.
Sorry, to post on yesterdays story, was out of the country for the past two weeks. JFK on the 4th of July was something else.
Last edited by runner140*; Jul 5, 2017 at 06:33 AM. Reason: add
Racer
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From: MA
I changed my coolant last weekend and found my radiator and AC condenser both full of grass and dirt. To clean them you don't actually have to pull the radiator. Pull the air deflector out in front of the condenser and you can lift it off the radiator where it hooks. You'll find you can now fit a garden hose and a sprayer between the condenser and radiator and power wash the crap out. First clean all the grass off with a brush. My car now runs 2-3 degrees cooler and never over 205.
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The Pantera must be given it's due respect. When I was 16 I heard an amazingly loud yet nicely cammed motor coming up the street I looked out to see one of the most radical looking and sounding cars. I asked my brother what it was an he said," Dude that's a Pantera!". Since that day I have always loved the Pantera. Oh throw a Cobra in there too for radical car tip of the hat.
But all that being said neither of those cars platforms flourished throughout time like the Corvette. They only became antiquated. But still bad ***!
But all that being said neither of those cars platforms flourished throughout time like the Corvette. They only became antiquated. But still bad ***!
1/4 mile/AutoX
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From: Buffalo Texas
The Pantera must be given it's due respect. When I was 16 I heard an amazingly loud yet nicely cammed motor coming up the street I looked out to see one of the most radical looking and sounding cars. I asked my brother what it was an he said," Dude that's a Pantera!". Since that day I have always loved the Pantera. Oh throw a Cobra in there too for radical car tip of the hat.
But all that being said neither of those cars platforms flourished throughout time like the Corvette. They only became antiquated. But still bad ***!
But all that being said neither of those cars platforms flourished throughout time like the Corvette. They only became antiquated. But still bad ***!
1/4 mile/AutoX
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From: Buffalo Texas
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Pantera not related to this topic...I was responding to some how "related thread".
That being said....I was having extraordinary high temp issues as well. Installed new radiator and new 180 stat. Still had intermittent elevated temps while stuck in traffic. Tried the Redline Wetter Water and brought temps to 190/ freeway and stuck in traffic temps down to 215.
That being said....I was having extraordinary high temp issues as well. Installed new radiator and new 180 stat. Still had intermittent elevated temps while stuck in traffic. Tried the Redline Wetter Water and brought temps to 190/ freeway and stuck in traffic temps down to 215.