2007 Coupe "Run on"
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Joined: Jul 2001
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From: Beverly Hills, CA USA
2007 Coupe "Run on"
My coupe has 450 miles and I filled it up at the local Shell station with 91 octane premium. Since that fill up, 2 separate times when I have pressed the ignition to off, the engine continues to "run on" for 3-5 seconds before finally shutting down. Is this because of bad gas, or is there some other problem? Thanks.
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From: YOU SEE ... I'M NOT CRAZY ...I'M JUST AHEAD OF THE CURVE
St. Jude Donor '09-'10
Does it "chug" (what used to call "dieseling") or simply run on smoothly?
Mine seems to take a "moment" between pushing the button and shut down, but if it is a significant time frame then that is not right.
If it continues to run smoothly, then there could be an issue with the switch itself.
I haven't heard of cars dieseling since fuel injection came along ... but I could be wrong.
Mine seems to take a "moment" between pushing the button and shut down, but if it is a significant time frame then that is not right.
If it continues to run smoothly, then there could be an issue with the switch itself.
I haven't heard of cars dieseling since fuel injection came along ... but I could be wrong.
Drifting
Joined: Jul 2006
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From: WA
1) A tank full of very SH*TTY gasoline
2) Your engine's timing might be out of adjustment
3) Excessive carbon build-up
4) Or... a combination of all the 3 items above!
So ...what VetVetter said was right ....your engine is "dieseling."
The LS2 & LS7 engines are designed to run on Super (91 octane and above).
Yeah, you can run lower octane fuel in your tank ....and it will appear to run just fine ....but since your engine was engineered to run BEST on 91 or higher octane fuel, your engine will not make the maximum power it was designed to produce on the 87 octane fuel.
Make sure you buy gasoline from a GOOD gas station. Chevron, Exxon and Union 76, are (from my own experience) always safe and good choices!
Check your engine's timing ...verify it's set where it's supposed to be at.
Good luck!
Last edited by Dbl6gun; Jun 12, 2007 at 08:07 PM.
Le Mans Master
Joined: Jul 2005
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If a fuel injected car diesels, there is a problem most likely with leaking/sticking fuel injectors. When you shut off a fuel injected car, the computer shuts down and stops firing the injectors thus shutting off the fuel that supplies a dieseling situation. A carbureutor will continue to feed fuel since there's nothing to stop it when you shut off the "electonics/electrical" system. I don't care how far the timing is off, how much deposits have built up, or how crappy the gas is, when you turn off a fuel injected engine, it can't diesel unless you have a problem...time to take if back to the dealer for some tests.
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Team Owner
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From: YOU SEE ... I'M NOT CRAZY ...I'M JUST AHEAD OF THE CURVE
St. Jude Donor '09-'10
And your guess is correct!
No you're not wrong, you are dead on too!
If a fuel injected car diesels, there is a problem most likely with leaking/sticking fuel injectors. When you shut off a fuel injected car, the computer shuts down and stops firing the injectors thus shutting off the fuel that supplies a dieseling situation. A carbureutor will continue to feed fuel since there's nothing to stop it when you shut off the "electonics/electrical" system. I don't care how far the timing is off, how much deposits have built up, or how crappy the gas is, when you turn off a fuel injected engine, it can't diesel unless you have a problem...time to take if back to the dealer for some tests.
No you're not wrong, you are dead on too!
If a fuel injected car diesels, there is a problem most likely with leaking/sticking fuel injectors. When you shut off a fuel injected car, the computer shuts down and stops firing the injectors thus shutting off the fuel that supplies a dieseling situation. A carbureutor will continue to feed fuel since there's nothing to stop it when you shut off the "electonics/electrical" system. I don't care how far the timing is off, how much deposits have built up, or how crappy the gas is, when you turn off a fuel injected engine, it can't diesel unless you have a problem...time to take if back to the dealer for some tests.
If it persisted I would definitely get it diagnosed properly.
good luck ... let us know what you find out mate.
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From: Beverly Hills, CA USA
I finally got a chance to bring the car in to the dealer to check out the problem AFTER first running the tank empty and then filling it up at a Chevron station. After the new tank fill up, the car continued to "run on" when I turned off the ignition about 85% of the time. The car now has 760 miles on it.
After the the car was at the dealer for about an hour in the electical department, they called to tell me they found 3 codes, but it wasn't electrical so they were sending it to "driveability" for further diagnosis.
After 2 days at the dealer, they just called me to say that they had 2 of their "master techs" working on it and haven't found any problem. They also can't explain what the 3 codes were that were found on Tuesday. This is unbelievable to me. Any suggestions?
After the the car was at the dealer for about an hour in the electical department, they called to tell me they found 3 codes, but it wasn't electrical so they were sending it to "driveability" for further diagnosis.
After 2 days at the dealer, they just called me to say that they had 2 of their "master techs" working on it and haven't found any problem. They also can't explain what the 3 codes were that were found on Tuesday. This is unbelievable to me. Any suggestions?
Race Director
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From: Virginia Bch VA
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St. Jude Donor '06
Never heard of that with a car with only 500 miles.
“Run on” is usually caused by excessive carbon build up. If you put cheep-o gas in for the first few tanks it's possible but not likely.
My advice to rid your motor from carbon would be to go to a country road and wind it out to the rev limiter at WOT. That should blow all the carbon out.
All gas sold is mandated by Federal Law, to have detergents. Sometimes delivery vehicles cut cost by eliminating additives. Against the law but it happens.
“Run on” is usually caused by excessive carbon build up. If you put cheep-o gas in for the first few tanks it's possible but not likely.
My advice to rid your motor from carbon would be to go to a country road and wind it out to the rev limiter at WOT. That should blow all the carbon out.
All gas sold is mandated by Federal Law, to have detergents. Sometimes delivery vehicles cut cost by eliminating additives. Against the law but it happens.
Melting Slicks
Joined: Jun 2006
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The knock sensor should pull timing--run on is knock, right away. Doesn't sound like the gas--I avoid Shell, use BP as an aside, but that's another story...
I bet the knock retard program is screwed up as part of the problem. Good luck!
I bet the knock retard program is screwed up as part of the problem. Good luck!
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From: Beverly Hills, CA USA
Well, I brought the car back to the dealer again today and they were able to figure out that the amp I had installed by AL & ED's here in Los Angeles was causing the problem the whole time. Apparently they hooked up the remote turn-on wire into the body control module and it was causing problems with the programs whenever the amp was on and the volume was turned above a certain level. Where is the best place to hook up that wire on an '07?
Le Mans Master
Joined: Jul 2005
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Well, I brought the car back to the dealer again today and they were able to figure out that the amp I had installed by AL & ED's here in Los Angeles was causing the problem the whole time. Apparently they hooked up the remote turn-on wire into the body control module and it was causing problems with the programs whenever the amp was on and the volume was turned above a certain level. Where is the best place to hook up that wire on an '07?
I figured it didn't have anything to do with knock causing run on or the "knock retard program".
