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Q: knocking and loud engine sound and poor acceleration.

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I have changed the fuel injectors , but still the car has a Lound and knocking sound. The acceleration is very poor and white smoke is emitted
My car has an automatic transmission.

A: Hello there, many faults will cause your 19...

Hello there, many faults will cause your 1994 Mercedes-Benz E320 to have a knocking sound and smoke. The most common is low oil level, spark plugs, fuel pump, plug wires, low oil pressure, piston rings, or engine mechanical damage. This vehicle should not be driven in its current condition until it is repaired. A qualified Technician such as one from YourMechanic will be able to diagnose your knocking noise and make any repairs required.

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