Coolant Temperature...I need your help :(
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,241
Likes: 0
From: Oceanside New York
Coolant Temperature...I need your help :(
Hey everyone. It seems that during idle, my coolant temperature rises up and above 200 degrees after a few minutes of idling, it's a slow and gradual increase.
Here's what i've done so far to see about preventing this (assuming that this is an issue):
- Flushed existing coolant using waterhose and blasts of air, refilled coolant with DexCool coolant and water mixture (50/50).
Anyone want to educate me as far as the temperature is supposed to be or what....i'm abit at a loss here and looking to you guys for answers.
Here's what i've done so far to see about preventing this (assuming that this is an issue):
- Flushed existing coolant using waterhose and blasts of air, refilled coolant with DexCool coolant and water mixture (50/50).
Anyone want to educate me as far as the temperature is supposed to be or what....i'm abit at a loss here and looking to you guys for answers.
Melting Slicks
Joined: Jun 2007
Posts: 2,537
Likes: 3
From: Chester County PA
St. Jude Donor '08
If sitting at idle my Z will reach around 230, until the fans come on, and then will start to decrease. When you turn the air cond. on the cooling fans will come right away. You can have the fan on temp reprogramed , so your fans will turn on sooner.
Another go thing is to check the radiator for road debris, which will block air flow.
Another go thing is to check the radiator for road debris, which will block air flow.
Race Director
Joined: Jun 2004
Posts: 19,459
Likes: 48
From: Schaumburg IL
CI 7-8-9-11 Veteran
St. Jude Donor '06-'10, '13
Your coolant temp is normal from what you are describing, a big factor is the ambient temp. In stop and go traffic in 80 degree weather, my coolant temps would get up to 225 or 230 until the second fan would kick on and bring them back down to 220 or so. The engine was designed to run that way.
You can check in between the ac condensor (sits in front of your radiator) and radiator to make sure there is not a lot of debris stuck up there. These cars act like vaccum cleaners since they sit so low to the ground they suck up a lot.
You can check in between the ac condensor (sits in front of your radiator) and radiator to make sure there is not a lot of debris stuck up there. These cars act like vaccum cleaners since they sit so low to the ground they suck up a lot.
Burning Brakes
Joined: Oct 2003
Posts: 1,106
Likes: 1
From: Foresters Falls(near Ottawa) Ont
You may not have a problem at all!!
RonJ ...
2018 Grand Sport
Joined: Nov 2005
Posts: 755
Likes: 21
From: Tarpon Springs Florida
That is normal. They were made to run at that temp and like it that way. but least you have clean coilant and radiator 
If you want you can put a 160 tstat in and get it tuned to turn your fans on earlier to help it run cooler little longer. but 220 is not abnormal.
If you want you can put a 160 tstat in and get it tuned to turn your fans on earlier to help it run cooler little longer. but 220 is not abnormal.
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Pro
Joined: Nov 2002
Posts: 717
Likes: 11
From: Pleasanton CA
I cleaned out the radiator and condenser, Installed a 180 thermostat (this only droped the temp to 190) The bigest help came when I had it tuned and had the fans start at a lower temp I think around 195 for the 1st fan. Prior to this temps were always 196-98 and 215-230 in summer traffic here in Calif. Adjusting the fans is the way to go, and the 180 thermostat helped out some. Now in the worst summer traffic it runs 200-205
Le Mans Master
Joined: Feb 2002
Posts: 6,937
Likes: 21
From: Waldorf MD
Normal
Corvette Cooling Fans Operation
The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).
Corvette Cooling Fans Operation
The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).
Race Director
Joined: Nov 2003
Posts: 12,346
Likes: 5
From: Mustang OK
Normal
Corvette Cooling Fans Operation
The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).
Corvette Cooling Fans Operation
The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph).
The cooling fan set temps above are for model years 2001 through 2004 C5s. The set temps for earlier model years (1997 through 2000) are somewhat different (the set temps being a little lower) and CharlieB's profile shows his car to be a 2000. However, the coolant temps that CharlieB says he is seeing at idle still appear to be well within the normal range for his model year.
Anyone wanting the factory set temps for the earlier model year C5s can either search the Forum or check the shop manual (try the Engine Section under Cooling System Description and Operation) specific to their car's model year.
Last edited by GrayC5; Dec 27, 2007 at 12:45 AM.
Team Owner
Joined: May 2001
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From: Virginia
St. Jude Donor '11
Thread Starter
Burning Brakes
Joined: Nov 2007
Posts: 1,241
Likes: 0
From: Oceanside New York
Thank you everyone for your help! I see that this may be normal. Yes, I have a 2000 Corvette. I want to add that I am in New York and the average temperature these days is around 40 degrees. I'm by no means in any warm weather area.
If I sit in idle, the car will steadily raise up to 200 degrees...then 203....then 205...at that point, I shut the car. While i'm driving, the car stays at a consistant 190/192 degrees. This normal as well?
If I sit in idle, the car will steadily raise up to 200 degrees...then 203....then 205...at that point, I shut the car. While i'm driving, the car stays at a consistant 190/192 degrees. This normal as well?
Race Director
Joined: Mar 2005
Posts: 10,034
Likes: 17
Thank you everyone for your help! I see that this may be normal. Yes, I have a 2000 Corvette. I want to add that I am in New York and the average temperature these days is around 40 degrees. I'm by no means in any warm weather area.
If I sit in idle, the car will steadily raise up to 200 degrees...then 203....then 205...at that point, I shut the car. While i'm driving, the car stays at a consistant 190/192 degrees. This normal as well?
If I sit in idle, the car will steadily raise up to 200 degrees...then 203....then 205...at that point, I shut the car. While i'm driving, the car stays at a consistant 190/192 degrees. This normal as well?
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Thank you everyone for your help! I see that this may be normal. Yes, I have a 2000 Corvette. I want to add that I am in New York and the average temperature these days is around 40 degrees. I'm by no means in any warm weather area.
If I sit in idle, the car will steadily raise up to 200 degrees...then 203....then 205...at that point, I shut the car. While i'm driving, the car stays at a consistant 190/192 degrees. This normal as well?
If I sit in idle, the car will steadily raise up to 200 degrees...then 203....then 205...at that point, I shut the car. While i'm driving, the car stays at a consistant 190/192 degrees. This normal as well?
I used to drive in Vegas and the fans would regularly cut in at 230 in stop go driving. Once they do the temperatures come straight back down. You'll probably do more harm by turning on and off than by letting the fans do the work. I suspect that you'll be pushed to get as warm as 230 in 40 degress OAT.