What are the reasons for severe engine shaking in reverse but not when moving forward?
2 Answers
The reasons for severe engine shaking in reverse but not when moving forward include excessive carbon deposits, fuel supply system malfunctions, and cylinder misfires. Excessive Carbon Deposits: If there is severe carbon buildup inside the engine cylinders, it can lead to clogged spark plugs or valves, directly causing the car to shake during idling. Fuel Supply System Malfunction: Unstable fuel pressure can easily cause fluctuations in the air-fuel mixture concentration, not only resulting in shaking but also causing unstable idling. First, consider replacing the fuel filter, as prolonged use may clog the filter element. Then, check the fuel pressure bypassing the fuel filter. If it is abnormal, the issue might lie with the fuel pump. Cylinder Misfire: If the ignition coil malfunctions or the spark plug fails to fire for some reason, the car will experience shaking.
As a veteran driver with over a decade of experience, I've encountered severe engine shaking during reverse gear several times while driving forward remains smooth. The most common cause is worn or damaged engine mounts/supports. When reversing, the engine tilts backward – if the rubber bushings are aged or cracked, they can't absorb vibrations properly, creating an earthquake-like sensation. For manual transmissions, unevenly worn clutch discs may slip and shudder under reverse gear's higher load. Automatic transmissions could have unstable fluid pressure or faulty valve body issues. Additionally, carbon-fouled spark plugs or aging ignition coils often reveal problems during high-load reverse maneuvers. Don't ignore these symptoms – worsening vibrations may damage suspension/drivetrain components, and misjudging reversing distances becomes hazardous. Start by visually inspecting mount conditions; if shaking persists, visit a professional repair shop immediately for thorough diagnostics. Safety first.