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Q: Rattle/ Knock from sounds like flywheel

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I've lost about 50% power if not more. When at a complete stop it acts like it has barely any power at all or just dies. Car doesn't run hot. Oil looks good no metal or debris. Used the listening stick and found that the non repetitive knocking or loud rattle is coming from the flywheel area. Is it possible that a bolt on the flywheel is lose or flywheel cracked? What could it be? Thanks

My car has 220000 miles.
My car has an automatic transmission.

Hi there:

Typically a loose flywheel is an indicator of other mechanical problems, ranging from a problem with the transmission converter (on an automatic) to the starter’s gear. The rattle could be coming from any of those components. In most cases, the lack of power would be related to the transmission component as opposed to the flywheel. It might be a good idea for you to contact a local mobile mechanic to come to your location and complete a car is slow to accelerate inspection; as you might have more than one problem going on with your Pontiac.

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