Overheating Horrors
Thread Starter
Melting Slicks
Joined: Apr 2006
Posts: 3,429
Likes: 0
From: Where all good things come to die. Detroit
Overheating Horrors
Hey everyone,
Today I had to drive my friend his keys that he locked in his Corvette at work. I drove the '86 and gave the keys to him and everything was fine but, as I started on my way back I started to have a problem. While driving on the freeway, I hit exactly 70 miles per hour, and my car wouldn't accelerate. It rumbled and quickly slowed down. I put it in neutral and restarted the car, and it ran long enough for me to pull off. Now when the car idles, its pretty low and the car shakes.
My engine is running around 230 and my coolant was around 210.
Ive heard that it could possibly be the gasoline vaporizing, but I am not sure. What should I do to get my car back on the road?
medic
Today I had to drive my friend his keys that he locked in his Corvette at work. I drove the '86 and gave the keys to him and everything was fine but, as I started on my way back I started to have a problem. While driving on the freeway, I hit exactly 70 miles per hour, and my car wouldn't accelerate. It rumbled and quickly slowed down. I put it in neutral and restarted the car, and it ran long enough for me to pull off. Now when the car idles, its pretty low and the car shakes.
My engine is running around 230 and my coolant was around 210.
Ive heard that it could possibly be the gasoline vaporizing, but I am not sure. What should I do to get my car back on the road?
medic
Le Mans Master
Joined: Apr 2000
Posts: 6,341
Likes: 1
From: Shelton CT
I'm not sure, but if the coolant were cooler than the oil temp I'd say you spun a bearing. Mine acted EXACTLY as you described when I spun a bearing on my '85 but my oiltemp was higher than coolant and even after cooling off it heated up once you push the gas pedal and put load on the war..
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Originally Posted by zr1fred
Don't panic, it could be a plugged cat, bad fuel pump, etc. 230 is not hot enough to do damage.
230 isn't very hot for an L98
Run some checks... Fuel Pressure would probably be first...
Team Owner
Joined: Sep 2001
Posts: 62,157
Likes: 1,732
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
This isnt an overheating issue.
This is something else, likely clogged up cat or fuel pump failure. Try hooking up a fuel pressure gauge and see what its reading. Look at the cats and see if they are turning red.
This is something else, likely clogged up cat or fuel pump failure. Try hooking up a fuel pressure gauge and see what its reading. Look at the cats and see if they are turning red.
Thread Starter
Melting Slicks
Joined: Apr 2006
Posts: 3,429
Likes: 0
From: Where all good things come to die. Detroit
It seemed that I was lacking something, since whenever I would go around a turn, my temperature would shoot up 3 to 4 degrees.
What should I check first?
Medic
What should I check first?
Medic
Le Mans Master
Joined: May 2005
Posts: 7,355
Likes: 2,279
From: Central Maryland
Get a timing light and fuel pressure gauge on that car first. See what they show. Take it from there.
As others have noted, you didn't overheat the engine, so relax. What you have is a driveability issue that can be diagonsed and corrected. A delta of ~20*F between oil and coolant temps is not uncommon. Your engine should be fine, but you will need to chase down the source of the problem and service as required.
Be well,
SJW
As others have noted, you didn't overheat the engine, so relax. What you have is a driveability issue that can be diagonsed and corrected. A delta of ~20*F between oil and coolant temps is not uncommon. Your engine should be fine, but you will need to chase down the source of the problem and service as required.
Be well,
SJW
Racer
Joined: Jul 2006
Posts: 327
Likes: 1
From: Trenton Ga
if your car does not have a oil cooler the oil temp will be a little higher than the coolant temp my oil temp is around 15 degrees hotter than the coolant at any given time after the car has been running for a few minutes. oil around 210 coolant around 197
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Racer
Joined: Jul 2006
Posts: 327
Likes: 1
From: Trenton Ga
if your car does not have a oil cooler the oil temp will be a little higher than the coolant temp my oil temp is around 15 degrees hotter than the coolant at any given time after the car has been running for a few minutes. oil around 210 coolant around 197 as a matter of fact when i went through 18 wheeler mechanic school they told us that 20 degrees was ok but no more than that but 18 wheeler have oil to water coolers
Instructor
Joined: May 2005
Posts: 132
Likes: 0
From: Torrington CT
When you hit the gas pedal in the driveway does it seem like the exhaust sounds normal. If cat is plugging up flow out exhaust will show up right there . Ive seen some so bad you could hardly feel any exhaust out the pipe compared to a properly running car.
Team Owner
Joined: Feb 2005
Posts: 20,111
Likes: 1
From: My redneck of the woods louisiana
umm 230 is not bad at all
mine went up to 299 which is the limit of the digital guage.
now i have serious problems
you have another problem for sure
do the checks advised by the others
mine went up to 299 which is the limit of the digital guage.
now i have serious problems
you have another problem for sure
do the checks advised by the others
Thread Starter
Melting Slicks
Joined: Apr 2006
Posts: 3,429
Likes: 0
From: Where all good things come to die. Detroit
UPDATE:
I can rule out that its an exhaust problem. Now that I think back prior to my new Y-pipe, when I went around a turn the car shut down. So I am thinking its a fuel problem, but where should I start?
Medic
I can rule out that its an exhaust problem. Now that I think back prior to my new Y-pipe, when I went around a turn the car shut down. So I am thinking its a fuel problem, but where should I start?
Medic
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
If you think fuel problem, get a fuel pressure guage and attach it to the schrader valve. Make sure it is tight so no leaks. Turn the key on (listen for the pump humm for 2 seconds) and observe the pressure, if any. If no pressure make sure the fuse is good and test the connector at the fuel pump with a test light. This will need to be done after using a hot wire from the battery to terminal G of the ALDL (first pin on bottom row). This will by pass the relay and send 12v to the fuel pump/circuit until the wire is removed. If you have 12v at the connector and no pressure pull the bad pump. If you have pressure take the ignition module and have it tested at Autozone. As others have stated the temps are fine.
The fuel pump relay is there to send power to the pump for 2 seconds. As soon as oil pressure reaches 4 psi when cranking the oil pressure switch (relay backup) sends power to the pump.
The fuel pump relay is there to send power to the pump for 2 seconds. As soon as oil pressure reaches 4 psi when cranking the oil pressure switch (relay backup) sends power to the pump.