When I turn on my car I hear a knocking noice and when I accelerate it's worse.and when I go it won't go fast..the noice sound like it's coming from under hood or by transmission
My car has a manual transmission.
If the noise is coming from the engine, then it sounds like you may have bad piston connecting rod bearing. This would account for the noise getting worse and very low power. If the noise never goes away it could also be internal to the transmission or clutch assembly, though if it was from the transmission, then it would go away when sitting stationary with the clutch depressed. Before any mystery noise can be determined, I would suggest have a qualified technician, such as one from YourMechanic, come and diagnose the noise in person. This way you can get a thorough diagnosis and know exactly what repairs are needed.
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