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Q: what could make my car have a knocking noise?

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My car has a really bad knocking noise in motor. It will still crank and run just has a really bad knock. I've already took valve covers off to check if it was a rocker arm and it wasn't so what could be my problem? I'm hoping it isn't a slung rod but I've been told it wouldn't crank and run if it was a slung rod. So any information would be greatly appreciated.

My car has 180000 miles.
My car has a manual transmission.

A loud knock inside the engine could be caused by a broken piston, bent rod, or any of several other possible causes. Just about any loud knock that is definitely coming from inside the engine block is not good. It would probably be best to have a certified mechanic take a look at the vehicle, as they will probably want to pull the oil pan to do an inspection. There are a few problems that can sound like they are coming from the engine, but may actually be something else, like a flywheel problem. Either way, you will probably want to consult a mechanic for their opinion. YourMechanic offers a repair and diagnosis service preformed by a certified mechanic that will commute to your location for this repair. YourMechanic offers a repair and diagnosis service preformed by a certified mechanic that will commute to your location to have your engine inspected.

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