What Causes Engine Shaking in Audi A4?

[SanWeston]

Audi A4 engine shaking is due to the air-fuel mixture not reaching the ideal ratio. Engine shaking occurs because the air-fuel mixture does not reach the ideal ratio: When one or more cylinders in the engine are malfunctioning, it directly causes the air-fuel mixture to fail to achieve the ideal ratio, resulting in shaking. Common causes: Spark plugs that have not been replaced for a long time may have excessive gaps, carbon buildup, or internal damage; one of the ignition coils in a cylinder may be damaged, causing that cylinder to malfunction; a short circuit inside the fuel pump may prevent low-pressure fuel from reaching the required supply pressure, leading to engine shaking or stalling; leaks in the engine intake system can cause engine shaking; excessive carbon buildup on the throttle valve, valves, or piston tops in cold conditions may be the cause; lack of cylinder pressure in one of the engine's cylinders due to poorly sealed valves or piston rings stuck with carbon buildup can also lead to engine shaking.