What Causes Neutral Gear Shaking?

[LaDelaney]

The reasons for engine shaking in neutral gear are as follows: 1. Poor gasoline quality: This is usually caused by filling up with low-quality gasoline at non-standard gas stations, leading to incomplete combustion of the air-fuel mixture during engine operation and triggering the engine fault light. While this does not affect driving safety, it may cause some degree of harm to the engine. 2. Oxygen sensor failure: Modern cars are equipped with two oxygen sensors, one before and one after the three-way catalytic converter. The front oxygen sensor detects the air-fuel ratio under different engine conditions, and the ECU adjusts the fuel injection amount and calculates the ignition timing based on this signal. The rear sensor mainly monitors the performance of the three-way catalytic converter. Therefore, if the oxygen sensor is damaged or the sensor connector is faulty or loose, it can cause the air-fuel mixture to become too lean or too rich, leading to the illumination of the fault light.

[VanJameson]

I've been driving for over a decade and have encountered neutral gear vibration issues several times. The main cause is aging engine mounts - when those rubber pads crack, they lose their damping effect, allowing the entire engine's vibration to transmit into the cabin. Another reason could be clogged fuel injectors causing uneven gasoline atomization, which leads to rough idling. Worn spark plugs are also a common culprit, especially those that haven't been replaced after 40,000-50,000 kilometers - unstable ignition causes shaking. Excessive carbon buildup in the throttle body can also lead to inaccurate air intake control, making the car jerk. A minor but important detail is loose engine support brackets, which can only be seen when the car is lifted. Remember to check these areas during regular maintenance to prevent vibration problems.

[AbelFitz]

Last time my car was shaking badly at idle while waiting at a red light, and the mechanic said it was due to cylinder misfire. Faulty spark plugs or ignition coils can cause individual cylinders to stop working, leading to unbalanced engine operation and natural vibration. Fuel system issues like a clogged fuel filter or unstable fuel pressure can cause the ECU to miscalculate fuel injection. Air intake system leaks can also cause this - even a small crack in rubber hoses can draw in excess air. Abnormal alternator voltage, loose belts causing unstable power generation, or sensor misjudgments can also lead to shaking. Oh, and excessive carbon buildup inside the engine changing the compression ratio is also very common. I'd suggest starting with simple checks like inspecting spark plugs and cleaning the throttle body first.

[DiLeila]

I often encounter neutral gear shaking when repairing cars. The most typical cause is aging engine mount rubber bushings; cracked rubber loses its damping effect. Issues in the ignition system, such as leaking ignition coils or aged wiring, can lead to poor ignition in a cylinder. Poor fuel quality with excessive gum can clog fuel injectors. A dirty mass airflow sensor misjudges intake volume, causing incorrect fuel injection commands from the ECU. Additionally, a stretched timing chain shifts valve opening/closing timing, resulting in incomplete combustion. It's recommended to focus on inspecting engine mount bushings, throttle position sensors, and the crankcase ventilation valve. Aging of these components can cause regular shaking and should be replaced promptly for a permanent fix.