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Old 07-20-2010, 04:06 AM
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antonio311
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Default Re: Knock sound when turning car off

Guys, it's always a good practice to let your car idle for 1 minute before shutting it off in your driveway....especially a turbo charged car. it allows the engine to circulate & cool down an engine especially after it's been driven hard.

Also a slight knocking clinging sound is normal upon shutting. As it's the exhaust system contracting after it's expansion during the heat up with the engine heat. It's a normal sound. Other knocking is not normal. Try a higher gasoline octane to limit engine knock & run-on after shut down.

Hope i helped a bit!