Overheating
Thread Starter
Instructor
Joined: Apr 2006
Posts: 128
Likes: 0
From: Washington IL
Overheating
99 C5 with STS. Car has started overheating, especially with the a/c on.
While waiting on new 160 deg stat I have run it without stat and still overheats. Seems to heat up very quickly.
With air running it jumps right up to 230+. If I turn off the air it will drop back down around 200.
Seems to me that it always ran in the 180 to 190 range. I believe it had a 180 stat in it.
Fluid level seems to be normal.
Could it be water pump(not leaking)?
Thanks for help.
While waiting on new 160 deg stat I have run it without stat and still overheats. Seems to heat up very quickly.
With air running it jumps right up to 230+. If I turn off the air it will drop back down around 200.
Seems to me that it always ran in the 180 to 190 range. I believe it had a 180 stat in it.
Fluid level seems to be normal.
Could it be water pump(not leaking)?
Thanks for help.
Melting Slicks
Joined: Jul 2007
Posts: 2,087
Likes: 11
From: Austin TX
Maybe try using straight distilled water instead of traditional coolant (might be worth trying the royal purple ice stuff since they just posted a video showing that by adding their stuff to the coolant system dropped temps. by a few degrees). If those don't help, the next step would be to grab a dewitts/spal fan upgrade as it flows double the cfm over stock. TPE has these on sale for a great price...just picked up one myself.
If none of the above help, next would be to do a radiator upgrade followed by an electric water pump
Melting Slicks
Joined: Mar 2008
Posts: 2,412
Likes: 4
From: Houston/Dayton Texas
what has changed? What have you done to the car or did it just start all of the sudden? make sure you have the air dam underneath your car, if its gone, replace it, fans turn off after 35 mph because they become ineffective.
CF Senior Moments Member
Joined: Jan 2004
Posts: 1,329
Likes: 1
From: Oklahoma City Oklahoma
Changed?
Did it start running hotter after you removed the thermostat - ? Maybe the water is not staying in the radiator long enough to get cooled properly? 
Also as suggested previously - be sure to check your air dam under car - if its gone then that will contribute to heat / not enough air flow directed etc. Happened to me long time ago - replaced air-dam problem solved.
Also as suggested previously - be sure to check your air dam under car - if its gone then that will contribute to heat / not enough air flow directed etc. Happened to me long time ago - replaced air-dam problem solved.
Thread Starter
Instructor
Joined: Apr 2006
Posts: 128
Likes: 0
From: Washington IL
It usually runs much cooler. 180-190. My bet is dirty radiator. I was on a gravel road a while back and it was really dusty and dirty and getting to that there was a lot of cut grass on the road.
Nothing has been changed on the car.
Nothing has been changed on the car.
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USMC (retired)
Joined: Aug 2004
Posts: 3,268
Likes: 6
From: Wimauma FL
But what if it still climbs and then steams out?
jobberone
Joined: Aug 2003
Posts: 2,062
Likes: 8
From: Kailua Kona HI
OP, get back to us after cleaning the radiator.
Semper Fi BTW. USMC 1968-71
USMC (retired)
Joined: Aug 2004
Posts: 3,268
Likes: 6
From: Wimauma FL
the rad is clean, brand new!
Thread Starter
Instructor
Joined: Apr 2006
Posts: 128
Likes: 0
From: Washington IL
Well it was trash in the radiator. I removed about a #10 can full of leaves and grass. Thanks to all of you for your replies.
I needed cooling system maintenance and wanted to go to a 160 stat anyway so no real wasted expenses.
Checking the radiator more regularly from now on.
Thanks again everyone!
I needed cooling system maintenance and wanted to go to a 160 stat anyway so no real wasted expenses.
Checking the radiator more regularly from now on.
Thanks again everyone!
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
Well it was trash in the radiator. I removed about a #10 can full of leaves and grass. Thanks to all of you for your replies.
I needed cooling system maintenance and wanted to go to a 160 stat anyway so no real wasted expenses.
Checking the radiator more regularly from now on.
Thanks again everyone!
I needed cooling system maintenance and wanted to go to a 160 stat anyway so no real wasted expenses.
Checking the radiator more regularly from now on.
Thanks again everyone!
Glad it was only that for you man.... Robert
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
Then you have a problem for sure. If you have a car that runs one temp and it starts running higher temps, then it's worth investigating, but if you know everything is as it should be and running high temps, it's time to start buying some parts.
ISIS SUCKS FAT CHOAD
Joined: Oct 2008
Posts: 8,124
Likes: 53
From: Earth, United States
Glad ya got it figured out man. I figured it was the radiator bring clogged with debris. Had identical issues with my first vette. In my case, the car was running around 190-210 on average and then all of the sudden it would run at 210-225. Then a month later it would consistently be at 230-240 and the coolant would boil over. I (just like you) began asking around the forums just looking at the radiator in the car u couldn't tell it was clogged. so I pulled the radiator and held it up to the sun light and it was slammed full of grass, dirt and other debris. Once I cleaned it out with a garden hose it was all good and the car went back to running 190-210
Last edited by MVP'S ZO6; Jul 24, 2011 at 09:47 PM.
