Sounds like a transmission/clutch issue to me. A bent exhaust? That sounds difficult to believe.
Help Need Advice!!!
Thread Starter
Drifting
Joined: Sep 2006
Posts: 1,571
Likes: 1
From: st.louis mo.
Help Need Advice!!!
had a bit of bad luck while leaving funfest saturday. me and some of the guys in my club were doing some spirited driving on the way home when i down-shift into the wrong gear and hit the rev-limiter really hard!(ouch) after that the car started to hesitate and backfire a bit at low rpm. also its very loud and sounds weird when i try to start it. so,as soon as i got off the highway it cut off and wouldnt start back up without me keeping my foot on the gas. i made it home so now its in my garage and im trying to figure out whats wrong before i take it to the shop and get screwed. a buddy of mine thinks i bent an exhaust valve. if anybody has any advice on what they think this may be i would appreciate it.
sorry for the long post
4got to mention it wiil not idle without my foot on the gas
sorry for the long post
4got to mention it wiil not idle without my foot on the gas
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From: In a parallel universe. Currently own 2014 Stingray Coupe.
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Sorry to hear about the problem. Not sure exactly what it might be. Hope you can get it fixed without spending a fortune.
Race Director
Joined: Jul 2004
Posts: 16,795
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From: Lake Havasu City, AZ
I would PM one of the tuners here, like Cajundude, or EnglandGreen or Doug@ECS.
They can probalby provide the best advice...
You might have done as little as blow out your high flow cats which changes backpressure and sound or done some more serious damage...
They can probalby provide the best advice...
You might have done as little as blow out your high flow cats which changes backpressure and sound or done some more serious damage...
Race Director
Joined: Apr 2005
Posts: 10,179
Likes: 2,306
From: Wesley Chapel, FL Las Vegas, NV
This is what I think. I hope I'm wrong.
You either bent a Valve (when the Valve hit the piston) and/or broke a Valve Spring. My bet is bent valve.
When you over rev, the valves float. (that means they do not return to the fully seated position before the piston comes up). This is common on engines that have a higher miles and the valve springs have weakened over time.
Do NOT try to start or drive the Vette. If you keep trying to run it you will break the valve, it will drop into the cylinder and do more damage.
If you're lucky the piston was not damaged and you'll get by with just repairing/changing the heads.
Do a Compression test. You can also pull the valve covers to inspect for visible damage.
Good Luck
You either bent a Valve (when the Valve hit the piston) and/or broke a Valve Spring. My bet is bent valve.
When you over rev, the valves float. (that means they do not return to the fully seated position before the piston comes up). This is common on engines that have a higher miles and the valve springs have weakened over time.
Do NOT try to start or drive the Vette. If you keep trying to run it you will break the valve, it will drop into the cylinder and do more damage.
If you're lucky the piston was not damaged and you'll get by with just repairing/changing the heads.
Do a Compression test. You can also pull the valve covers to inspect for visible damage.
Good Luck
Last edited by Vega$Vette; Sep 24, 2007 at 11:35 AM.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
I agree with pulling the valve covers. Check for valves stuck or jammed. When you hit the rev limiter in the PCM, I think it kills the fuel only, but I'm not sure. Its going to be difficult to do a compression test without turning the engine over but you might try something simple...have someone manually turn it over at the crank while you are putting a finger over each spark plug hole. If one or more doesn't have any pressure, you know where to start.
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Le Mans Master
Joined: Aug 2001
Posts: 8,145
Likes: 1
From: Bradenton FLORIDA
This is what I think. I hope I'm wrong.
You either bent a Valve (when the Valve hit the piston) and/or broke a Valve Spring. My bet is bent valve.
When you over rev, the valves float. (that means they do not return to the fully seated position before the piston comes up). This is common on engines that have a higher miles and the valve springs have weakened over time.
Do NOT try to start or drive the Vette. If you keep trying to run it you will break the valve, it will drop into the cylinder and do more damage.
If you're lucky the piston was not damaged and you'll get by with just repairing/changing the heads.
Do a Compression test. You can also pull the valve covers to inspect for visible damage.
Good Luck
You either bent a Valve (when the Valve hit the piston) and/or broke a Valve Spring. My bet is bent valve.
When you over rev, the valves float. (that means they do not return to the fully seated position before the piston comes up). This is common on engines that have a higher miles and the valve springs have weakened over time.
Do NOT try to start or drive the Vette. If you keep trying to run it you will break the valve, it will drop into the cylinder and do more damage.
If you're lucky the piston was not damaged and you'll get by with just repairing/changing the heads.
Do a Compression test. You can also pull the valve covers to inspect for visible damage.
Good Luck
Melting Slicks
Joined: Apr 2007
Posts: 3,290
Likes: 0
From: Willow Springs IL
Could have bent a pushrod also. Very least pull the valve covers and check the springs out. Not a bad idea to pull the pushrods out one by one and check them. If the springs and pushrods look fine then you'll have to pull the heads and check the valves. Chances are that if you bent a valve there would also be pushrod or spring damage though. Good Luck!
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
This is what I think. I hope I'm wrong.
You either bent a Valve (when the Valve hit the piston) and/or broke a Valve Spring. My bet is bent valve.
When you over rev, the valves float. (that means they do not return to the fully seated position before the piston comes up). This is common on engines that have a higher miles and the valve springs have weakened over time.
Do NOT try to start or drive the Vette. If you keep trying to run it you will break the valve, it will drop into the cylinder and do more damage.
If you're lucky the piston was not damaged and you'll get by with just repairing/changing the heads.
Do a Compression test. You can also pull the valve covers to inspect for visible damage.
Good Luck
You either bent a Valve (when the Valve hit the piston) and/or broke a Valve Spring. My bet is bent valve.
When you over rev, the valves float. (that means they do not return to the fully seated position before the piston comes up). This is common on engines that have a higher miles and the valve springs have weakened over time.
Do NOT try to start or drive the Vette. If you keep trying to run it you will break the valve, it will drop into the cylinder and do more damage.
If you're lucky the piston was not damaged and you'll get by with just repairing/changing the heads.
Do a Compression test. You can also pull the valve covers to inspect for visible damage.
Good Luck
or possibly bent rod Hope I'm wrong. I would not drive or try and start it either without pulling the valve covers and checking.
Advanced
Joined: Oct 2004
Posts: 54
Likes: 0
From: San Rafael CA
Over-rev
A fellow club member just did the same thing and bent lots of valves.
He had all the valves replaced and took the sharp edges off the piston tops.
Runs like new.
Hope it didn't do more damage than that, pull the heads and see what's up.
He had all the valves replaced and took the sharp edges off the piston tops.
Runs like new.
Hope it didn't do more damage than that, pull the heads and see what's up.
Melting Slicks
Joined: May 2007
Posts: 2,533
Likes: 1
From: North Aurora IL
That sucks.....But my guess would be valves as well...and I would say it's more than just one.....Let's hope you didnt mess up the pistons here.....Guess the positive out look on this all is you can always upgrade once you find out what you tore up....
Instructor
Joined: Aug 2007
Posts: 237
Likes: 0
From: Palmdale California
Pull the engine covers off (whatever they're called) and start the car. Grab a long screwdriver and put it up to the valve covers one by one. When you do that, put your ear up against the screw driver. If there is something wrong with the valve train you will feel & hear it.
A compression check will instantly clue you in....
At least you didn't drop a valve. That would make an aweful racket. I also don't think that a valve spring broke because that probably would have caused the valve to drop.
Did you get a code or check engine light? Chances are that you would get a weird code for a cylinder that has lost pressure.
Good luck!
A compression check will instantly clue you in....
At least you didn't drop a valve. That would make an aweful racket. I also don't think that a valve spring broke because that probably would have caused the valve to drop.
Did you get a code or check engine light? Chances are that you would get a weird code for a cylinder that has lost pressure.
Good luck!
Melting Slicks
Joined: Jan 2007
Posts: 3,021
Likes: 133
From: Conejo Valley CA
Thread Starter
Drifting
Joined: Sep 2006
Posts: 1,571
Likes: 1
From: st.louis mo.
engine light
i didnt get a check engine light until i got home cut it off and started it back up.
whats up flk-jr bout time you got back on here. and yeah i saw that post about the burning vett,man thats gotta suck
whats up flk-jr bout time you got back on here. and yeah i saw that post about the burning vett,man thats gotta suck