Still overheating-major problem??
Thread Starter
Pro
Joined: Jul 2007
Posts: 524
Likes: 8
From: Houston Tx
Still overheating-major problem??
my 99 coupe is still overheating after pressure test for coolant leak (none found) coolant flush, new t stat, coolant temp sensor, fans checked...etc. So the fans kick on when they should and it doesnt leak coolant. it stays cool at idle but when i drive it she slowly overheats and i am forced to pull over. i had to tow it to freedom chevy in san antonio. any body have any idea?
Le Mans Master
Joined: Mar 2002
Posts: 8,466
Likes: 51
St. Jude Donor '17
ran into a similar problem after i had replaced radiator hoses.
Turns out that the hose was not twisted in the right position causing an up hill flow and possible "air hammer".
the other common issues is garbage stuck in front of the radiator shroud.
crawl up under it and check for junk stuck in the fins and use a water hose and flush the fins.
Turns out that the hose was not twisted in the right position causing an up hill flow and possible "air hammer".
the other common issues is garbage stuck in front of the radiator shroud.
crawl up under it and check for junk stuck in the fins and use a water hose and flush the fins.
Melting Slicks
Joined: Sep 2011
Posts: 2,258
Likes: 543
From: Appleton WI
Have you checked to make sure the radiator is not plugged? You said you had the system flushed but did they verify the radiator is functioning properly?
When I was a kid, I killed a car because the radiator was plugged and my idiot light didn't work. I had overheated and could not find the cause so I changed the coolant and oil. After filling with new coolant I verified flow by opening the cap on the radiator. It was flowing great. What I didn't know to do was feel the face of the radiator to verify the whole radiator was an even temperature. The lower half of the radiator was plugged so I only had half the cooling efficiency.
Get your engine up to operating temp and then feel the front of the radiator from top to bottom. (be careful not to burn yourself) If a section of radiator is plugged, it will be noticeably cooler than the rest.
Just a thought...
When I was a kid, I killed a car because the radiator was plugged and my idiot light didn't work. I had overheated and could not find the cause so I changed the coolant and oil. After filling with new coolant I verified flow by opening the cap on the radiator. It was flowing great. What I didn't know to do was feel the face of the radiator to verify the whole radiator was an even temperature. The lower half of the radiator was plugged so I only had half the cooling efficiency.
Get your engine up to operating temp and then feel the front of the radiator from top to bottom. (be careful not to burn yourself) If a section of radiator is plugged, it will be noticeably cooler than the rest.
Just a thought...
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
I'll bet you a buck.....
I'll bet you....that you have either a clogged up radiator (needs to be pulled out and pressure sprayed clean). or you have an air bubble....in the system. Both are easy fixes.
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Burning Brakes
Joined: Apr 2009
Posts: 778
Likes: 1
From: Chantilly VA
I had plugged radiator, from the coolant turning to gel. But I had opposite over heating problem. Ran cool on highway but over heated fast sitting in traffic. A presser flush on radiator cured me, luckily. 
Thread Starter
Pro
Joined: Jul 2007
Posts: 524
Likes: 8
From: Houston Tx
well dealer called and said the crappy autozone tstat i used was part of the problem but the major thing was that the radiator cradle was all jacked up under the car and wasnt allowing air to flow up during highway speeds. he said it was bent and missing all kinds of hardware so that was blocking air flow. had to get the parts from detroit and the whole thing is gona cost a pretty penny. only had the car 45 days and havent even got a chance to enjoy it. lesson learned to have a professional do a complete pre purchase inspection on the next one...bummer
Le Mans Master
Joined: Mar 2002
Posts: 8,466
Likes: 51
St. Jude Donor '17
well dealer called and said the crappy autozone tstat i used was part of the problem but the major thing was that the radiator cradle was all jacked up under the car and wasnt allowing air to flow up during highway speeds. he said it was bent and missing all kinds of hardware so that was blocking air flow. had to get the parts from detroit and the whole thing is gona cost a pretty penny. only had the car 45 days and havent even got a chance to enjoy it. lesson learned to have a professional do a complete pre purchase inspection on the next one...bummer
Take your vette up to Biffs Burgers on Toperwein on a friday night behind the waterburger.
Go talk to all the other guys with vettes and have em take a peek.