Rough When Turned Off
Thread Starter
Instructor
Joined: Jun 2003
Posts: 212
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From: Orland IL
Rough When Turned Off
When I shut my 98 LS1 engine off, it shuts off rough.. a little like an old carb would try to keep running. It only has 40k on it and zero mods and no accesories on when i shutt off, do i need a tune up?
Safety Car
Joined: Feb 2002
Posts: 4,942
Likes: 7
From: Gaffney, S.C.
Re: Rough When Turned Off (Sweet98)
I doubt if tuning will help your situation. It sounds as though you may have some low octane fuel, excess carbon buildup in your cylinders, excessively high idle speed, or some dirty or leaking fuel injectors. When you shut your engine off you no longer have spark to your plugs so that eliminates a tuning problem.
Melting Slicks
Joined: Feb 2002
Posts: 2,290
Likes: 1
From: Ca
Re: Rough When Turned Off (irfgt)
There is NOTHING wrong with your car. You have a stick shift don't you??? That is just how the 6spds shut down when you turn the car off. Put the clutch to the floor when you turn the car off and the lugging down will be reduced. That is completely natural for yoru vette to do.
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Robert
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Robert
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Thread Starter
Instructor
Joined: Jun 2003
Posts: 212
Likes: 0
From: Orland IL
Re: Rough When Turned Off (mike76002)
If I turn it off imediately when i put it in park its ok. If i leave it sit a minute then turn it off, then its rough. The idle seems normally low and running fine.
1st Gear
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Melting Slicks
Joined: Sep 2021
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I doubt if tuning will help your situation. It sounds as though you may have some low octane fuel, excess carbon buildup in your cylinders, excessively high idle speed, or some dirty or leaking fuel injectors. When you shut your engine off you no longer have spark to your plugs so that eliminates a tuning problem.
