Rough and won't idle
Thread Starter
Instructor
Joined: Oct 2008
Posts: 133
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From: Eastchester NY
Rough and won't idle
I am looking for suggestions. C5 corvette with a TVS2300 magnuson supercharger. Methanol injection in the air bridge after the MAF sensor. The car will not idle and runs extremely rough. It throws a current p0300 misfire code and no other codes. I have checked the coils and they are firing fine. I replaced the plugs and plug wires with no improvement. I don't see any issues with the ground wires. There do not seem to be any vacuum leaks. Can a broken valve spring cause this?
The misfire code has been present off and on for a while. By that i mean sometimes as a history code and sometimes current. Recently it threw an MAF code P0101 but that has gone away. I cleaned the MAF sensor and that may be the reason why the p0101 code went away.
The car can be driven but will not idle and runs really really rough under any sort of throttle. Thanks in advance for any suggestions.
The misfire code has been present off and on for a while. By that i mean sometimes as a history code and sometimes current. Recently it threw an MAF code P0101 but that has gone away. I cleaned the MAF sensor and that may be the reason why the p0101 code went away.
The car can be driven but will not idle and runs really really rough under any sort of throttle. Thanks in advance for any suggestions.
Team Owner
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you may be onto it....sounds like a recent post same type of symptoms....time to pull the covers and see
Burning Brakes
Joined: Jan 2008
Posts: 941
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From: Grand Rapids MI
So this problem is intermittent or continuous?
How did you check for vacuum leaks?
If this problem is constant, and there are truly no vacuum leaks, I would do a compression test ASAP. Also pull the valve covers to visually inspect the springs. There is not much else that can be troubleshot until you confirm those things.
Jack
How did you check for vacuum leaks?
If this problem is constant, and there are truly no vacuum leaks, I would do a compression test ASAP. Also pull the valve covers to visually inspect the springs. There is not much else that can be troubleshot until you confirm those things.
Jack
Thread Starter
Instructor
Joined: Oct 2008
Posts: 133
Likes: 0
From: Eastchester NY
So this problem is intermittent or continuous?
How did you check for vacuum leaks?
If this problem is constant, and there are truly no vacuum leaks, I would do a compression test ASAP. Also pull the valve covers to visually inspect the springs. There is not much else that can be troubleshot until you confirm those things.
Jack
How did you check for vacuum leaks?
If this problem is constant, and there are truly no vacuum leaks, I would do a compression test ASAP. Also pull the valve covers to visually inspect the springs. There is not much else that can be troubleshot until you confirm those things.
Jack
Burning Brakes
Joined: Jan 2008
Posts: 941
Likes: 3
From: Grand Rapids MI
Did something happen to the car? Was it over-revved at any point? Or did this problem just occur out of nowhere?
Jack
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Joined: Oct 2008
Posts: 133
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From: Eastchester NY
Drifting
Joined: Nov 2005
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From: NW Chicago
St. Jude Donor '12-'13-'14-'15
Just went through the exact same as you are describing, changed wires and plugs, checked grounds and for vaccum leaks. Broken intake spring on #2. I wouldn't start it anymore until you check the springs. I'm doing the trunion upgrade while I'm in there. Just waiting for the springs to arrive. Good luck and I hope all is intact in your valvetrain. By the way I was just going to a group lunch, driving very old lady-like, when **** hit the fan. Had it towed home from lunch on suspicion of it being a valve spring.
Last edited by punz; Nov 11, 2012 at 08:02 PM.
