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Q: Getting knocking sound when engine is idling from the floor front and side of the engine

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2004 Lincoln Aviator knocking sound coming towards the lower front coming from the lower front as well a side of engine. When Engine is in drive and moving beyond 10 miles an hour the knocking stops. And it seems to decrease as the car slows down

My car has 230248 miles.
My car has an automatic transmission.

Hello, thank you for writing in. The knocking is going to sound worse at idle because the number of combustion cycles happening is less than when you are accelerating or maintaining a higher RPM. With that being said, engine knock is most commonly attributed to a poor explosion in the cylinder(s). This can be caused by a spark issues, a fuel issue (like the wrong type of fuel for the engine, or poor fuel quality), bad valve seals, or even a bad knock sensor. All of these components will need to be tested separately. Start with the spark system as it is typically easiest to repair, and it is a heavily uses system that needs constant maintenance. For more help, contact our service department to schedule an appointment.

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