Coolant Temperature Too High?
Thread Starter
Heel & Toe
Joined: Mar 2006
Posts: 20
Likes: 0
Coolant Temperature Too High?
Hi,
Everytime I drive my '99 torch red corvette, the coolant temperature gets hot very fast. Even after a few minutes of driving, the coolant temperature will reach 160 degrees. After a 30 minute drive, it will push 220 degrees.
Also, the oil pressure can reach 44 psi even after a few minutes on the road.
Should I be alarmed, or is this normal? I don't race my vette, and I don't even have a single mod on my car.
Will flushing the coolant help? Please help me out if you can.
-Clearcoat
Everytime I drive my '99 torch red corvette, the coolant temperature gets hot very fast. Even after a few minutes of driving, the coolant temperature will reach 160 degrees. After a 30 minute drive, it will push 220 degrees.
Also, the oil pressure can reach 44 psi even after a few minutes on the road.
Should I be alarmed, or is this normal? I don't race my vette, and I don't even have a single mod on my car.
Will flushing the coolant help? Please help me out if you can.
-Clearcoat
Drifting
Joined: May 2006
Posts: 1,616
Likes: 1
From: Minnesota
30 minute "drive" meaning > 35 mph most of the time? I think that's way too high. 30 minutes of sitting in traffic/city driving with outside temp @ 85? 220 is not too high.
In normal driving I rarely get above say 192. Even when it's 80+ outside.
Never hurts to flush if it's due.
In normal driving I rarely get above say 192. Even when it's 80+ outside.
Never hurts to flush if it's due.
Thread Starter
Heel & Toe
Joined: Mar 2006
Posts: 20
Likes: 0
Hi,
I live in Dallas, Texas, and I have been driving with no traffic.
I get the 220 degrees for the coolant temperatue when driving during outside temperatures between 40 and 70 degrees.
Today, it was 32 degrees, and my coolant temp managed to reached between 160 - 190 degrees after about 5 - 10 minutes of driving.
-Clearcoat
I live in Dallas, Texas, and I have been driving with no traffic.
I get the 220 degrees for the coolant temperatue when driving during outside temperatures between 40 and 70 degrees.
Today, it was 32 degrees, and my coolant temp managed to reached between 160 - 190 degrees after about 5 - 10 minutes of driving.
-Clearcoat
Melting Slicks
Joined: Sep 2003
Posts: 2,458
Likes: 105
From: Northville Michigan
What temperature would you like to have the coolant stabilize at?
GM Race Engineering states that the LS engine family makes its best power when the coolant temperature is between 180 and 189 degrees. On the C6R race Corvettes, the drivers are instructed to turn the engine off it the coolant temperature reaches 190 degrees.
GM Race Engineering states that the LS engine family makes its best power when the coolant temperature is between 180 and 189 degrees. On the C6R race Corvettes, the drivers are instructed to turn the engine off it the coolant temperature reaches 190 degrees.
Safety Car
Joined: Jul 2001
Posts: 4,661
Likes: 67
From: Ocean Springs MS
Hi,
I live in Dallas, Texas, and I have been driving with no traffic.
I get the 220 degrees for the coolant temperatue when driving during outside temperatures between 40 and 70 degrees.
Today, it was 32 degrees, and my coolant temp managed to reached between 160 - 190 degrees after about 5 - 10 minutes of driving.
-Clearcoat
I live in Dallas, Texas, and I have been driving with no traffic.
I get the 220 degrees for the coolant temperatue when driving during outside temperatures between 40 and 70 degrees.
Today, it was 32 degrees, and my coolant temp managed to reached between 160 - 190 degrees after about 5 - 10 minutes of driving.
-Clearcoat
However, the min temperature on your system, if it is stock will be around 190 deg F, as that is the thermostat GM puts in it. If you have any blockage, the system will get to that temp quicker, which sounds like your problem. The Stat controls the min temperature of your system. Even a low temp thermostat won't help if your system has air or coolant flow problems.
Last edited by fdxpilot; Jan 5, 2009 at 08:12 PM.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
One usual cause of higher coolant temps, not that your's is that high, but usually is debris in the condensor coils plugging up the airflow. Sometimes plastic bags and other junk and most of the time, a gazzillion small rocks in the vanes. They can be washed out or blown out from the reverse direction with either an air-wand or water wand of some sort. Other than that, as already stated, check the fans for normal operation. Typcially they turn on at low-speed around 225 degrees I think and at something like 235 degrees, they go to high-speed. Both fans run when they are running. To verify their operation, simply turn on the Hvac. They will run unless the outside air temp gets down to somewhere around 42 to 38 degrees at which time, they will shut off.
Team Owner
Joined: Mar 2001
Posts: 21,325
Likes: 3,841
From: small town in S.E Pa. PA
St. Jude Donor '03-'04
A C5 is a bottom feeder... Clean your AC condensor fins which sit directly in front of your radiator, which also needs to be cleaned, they sit piggy back with an inch and a half in between the two .. Your temps are far from abnormal.. but indicate there is a restriction in the heat transfer rate. I clean my cond/radiator once a year and pull a year's debris of bugs, leaves, dirt, paper and sand, which accumulate in the cooling vanes. Every year I remove a half cup of this debris.
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Tech Contributor
Joined: Oct 1999
Posts: 41,066
Likes: 9,831
From: Charlotte, NC (formerly Endicott, NY)
Hi,
I live in Dallas, Texas, and I have been driving with no traffic.
I get the 220 degrees for the coolant temperatue when driving during outside temperatures between 40 and 70 degrees.
Today, it was 32 degrees, and my coolant temp managed to reached between 160 - 190 degrees after about 5 - 10 minutes of driving.
-Clearcoat
I live in Dallas, Texas, and I have been driving with no traffic.
I get the 220 degrees for the coolant temperatue when driving during outside temperatures between 40 and 70 degrees.
Today, it was 32 degrees, and my coolant temp managed to reached between 160 - 190 degrees after about 5 - 10 minutes of driving.
-Clearcoat
Bill
Burning Brakes
Joined: Apr 2007
Posts: 966
Likes: 9
From: Phoenix AZ
Early last year I started to see temps of 220+ in 75 degree weather while on the freeway. I cleaned the condenser and radiator, flushed coolant and replaced the thermostat, and have been comfortable at 192-194 ever since.
As for oil pressure, I generally see 32-35 psi at idle, with oil temp around 205 degrees, IIRC.
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
While checking for debris in the condensor and radiator as well as making sure your air dam is in place are good ideas and will probably offer an improvement for your cooling, it's important to remember that if your car is stock and the fans have not been reprogrammed that the factory setting will not let the first cooling fan come on until the coolant reaches 225 degrees.
And while the C6R engines are optimized to run between 180 and 190 degrees it's extremely important to remember that your engine is not a C6R and shares little to no parts of that race engine.
And while the C6R engines are optimized to run between 180 and 190 degrees it's extremely important to remember that your engine is not a C6R and shares little to no parts of that race engine.
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
It is possible that your thermostat is not opening completely.
It does not seem unusual for the engine to get to 160 deg. fairly quickly, but once it gets to 195 deg. the thermostat should open and the temperature should be relatively constant with a low ambient temperature.
High oil pressure is not due to high engine temperature. In fact, the oil pressure is higher when the oil is cold and the pressure should come down as it heats up. At a given temperature, the oil pressure should increase with RPM, not coolant temperature.
It does not seem unusual for the engine to get to 160 deg. fairly quickly, but once it gets to 195 deg. the thermostat should open and the temperature should be relatively constant with a low ambient temperature.
High oil pressure is not due to high engine temperature. In fact, the oil pressure is higher when the oil is cold and the pressure should come down as it heats up. At a given temperature, the oil pressure should increase with RPM, not coolant temperature.
Last edited by TEXHAWK0; Jan 6, 2009 at 04:16 PM.
Tech Contributor
Joined: Jan 2007
Posts: 19,518
Likes: 1,189
From: Dyer, IN
Thread Starter
Heel & Toe
Joined: Mar 2006
Posts: 20
Likes: 0
Thanks for you help.
Hi Everyone,
Thanks for you help so far with my engine cooling issues. I read in consumer reports that the '99 vette gets a full black circle for engine cooling so I am cautious.
The air dam in my car is fine. Is there somewhere on the internet or a book that can show me how to clean the debris in the condersor coils, condensor fins, and radiator in my C5?
I am also getting a "low coolant" warning while driving, but the coolant level in the reservoir seems to be at the proper level. I am going to have a radiator shop flush the coolant this weekend.
thanks again
-Neil
Thanks for you help so far with my engine cooling issues. I read in consumer reports that the '99 vette gets a full black circle for engine cooling so I am cautious.
The air dam in my car is fine. Is there somewhere on the internet or a book that can show me how to clean the debris in the condersor coils, condensor fins, and radiator in my C5?
I am also getting a "low coolant" warning while driving, but the coolant level in the reservoir seems to be at the proper level. I am going to have a radiator shop flush the coolant this weekend.
thanks again
-Neil
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
A C5 is a bottom feeder... Clean your AC condensor fins which sit directly in front of your radiator, which also needs to be cleaned, they sit piggy back with an inch and a half in between the two .. Your temps are far from abnormal.. but indicate there is a restriction in the heat transfer rate. I clean my cond/radiator once a year and pull a year's debris of bugs, leaves, dirt, paper and sand, which accumulate in the cooling vanes. Every year I remove a half cup of this debris.
Our cars (especially lowered cars) are huge vacum cleaners.. Its unbelievable what may be in between rhe 2 condensor/radiator fins. You will have to pull the fan shroud off.. The part that says " caution fan" and the air bridge.. Use compressed air or a hose/sprayer.. Spray up and down from back side of fins.. Be real carefull not to bend the fins.. Too much pressure will easily bend them Try an experiment... Make a fist and bang on the front bumper with the back of your fist... Make sure the garage floor is clean... Hit the bumper 4-5 times then look at the floor under the radiator... I bet your clean floor is not clean anymore
Last edited by David426; Jan 9, 2009 at 08:08 PM.
