Q: Knocking noise under hood

asked by on August 12, 2016

When the car cranks and while running, there is a knocking noise that comes from under the hood.

My car has 100000 miles.
My car has an automatic transmission.

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Without actually hearing the noise, it is difficult to determine the exact cause of your concern. It could be low oil pressure, valve adjustment, bearing failure, etc. I suggest having a certified technician, like one from YourMechanic, determine the exact cause the noise.

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