What Causes Engine Idle Shaking and Stalling?

[OIris]

The reasons for engine idle shaking and stalling: 1. Severe engine carbon buildup. The most common cause of car shaking is a dirty throttle body or excessive carbon deposits in the fuel injectors. 2. Ignition system issues. Check the condition of the spark plugs, high-voltage wires, and ignition coils. Poor performance of the ignition system or weak spark plug firing can also lead to such malfunctions. 3. Unstable fuel pressure. If you've already cleaned the engine carbon buildup, throttle body, replaced gaskets and spark plugs, but still experience body shaking at idle, it's recommended to visit a 4S shop to check the fuel supply pressure and intake pressure sensor. Abnormal fuel pump pressure or incorrect readings/malfunction of the intake pressure sensor can cause body shaking. 4. Aging engine components. Car shaking can also be related to worn engine mounts (also known as engine cushions). Engine mounts essentially serve as the engine's vibration damping system, absorbing minor vibrations during operation. If the engine mounts fail, these vibrations will transfer to the steering wheel and cabin, causing shaking at idle.

[DiEmersyn]

I've been driving for over a decade and have seen plenty of idle stalling cases. The most common causes are spark plugs that have been used too long or gotten dirty, resulting in unstable ignition; fuel system blockages or aging fuel pumps causing insufficient fuel supply; and excessive carbon buildup in the throttle body preventing air from entering the engine. Additionally, faulty sensors like the mass airflow sensor can disrupt the air-fuel mixture ratio. I remember one time my car shook violently and stalled on the road - it took forever to fix, turned out to be a burnt ignition coil. My advice: don't ignore idle vibrations. Early inspection and part replacement helps, and throttle body cleaning usually works well to avoid expensive major repairs. Always listen to your engine sounds while driving - checking at the first sign of trouble prevents many issues.

[EvangelineAnn]

Engine shaking, swaying, or even stalling at idle is primarily caused by combustion imbalance. Issues in the ignition system, such as spark plug carbon buildup or deteriorating ignition coils, can affect ignition efficiency. In the fuel system, low fuel pump pressure or a clogged filter may disrupt fuel supply. Excessive carbon deposits in the intake tract, especially the idle control valve, can lead to unstable air flow regulation. From my experience, cleaning the idle control valve and checking sensors (like the oxygen sensor) can alleviate shaking. Prolonged neglect can result in higher fuel consumption and increased pollution, so regular maintenance and cleaning are essential. Replacing a faulty component or adjusting the air-fuel mixture often helps significantly. The key is not to delay repairs too long to avoid engine damage. For minor issues, DIY cleaning during maintenance is recommended.

[MirandaMarie]

Idle shaking and stalling are mostly caused by engine fuel supply or ignition issues. For example, carbon buildup blocking the throttle or intake pipe; spark plugs burned out and failing to ignite; fuel line obstruction interrupting fuel supply. Once this occurs, the engine becomes unstable and eventually stops working. It is recommended to immediately check basic components, replace spark plugs or clean the air filter. Delaying may damage more systems, accelerate wear, increase fuel consumption and emissions. Simple maintenance can prevent major repairs.

[McAddyson]

Idle shaking and stalling are extremely dangerous and can easily lead to accidents. Common causes include poor ignition such as faulty spark plugs, or insufficient fuel pressure due to a weak fuel pump. Malfunctioning sensors like the throttle position sensor can also disrupt control. I always remind car owners to repair these issues promptly to avoid stalling and losing power on the road, which could cause accidents. You can start by checking and cleaning carbon deposits yourself. For serious cases, visit a professional shop to use diagnostic tools, check error codes, and replace parts. Remember, safety comes first—don’t delay repairs to save money. Regular maintenance like oil changes and valve cleaning can reduce this risk.