What Causes Engine Idle Vibration When the Car is Warm?

[JohnnyLee]

Hot engine idle vibration is caused by: 1. An inappropriate air-fuel mixture ratio in the car engine compartment, which affects engine vibration; 2. Spark plugs that have been used for too long, aging ignition coils, aging high-voltage wires of the spark plugs, and leakage issues that can reduce ignition capability; 3. Carbon deposits formed on the valves and intake ports inside the engine. Carbon deposits can absorb a significant amount of fuel, affecting the sprayed air-fuel mixture, resulting in reduced car power and malfunctioning of the water temperature sensor. The car engine is the device that provides power to the car, determining its power, fuel efficiency, stability, and environmental friendliness.

[ReaganDella]

Engine idling shake when the car is warm is quite common in my opinion, mostly due to issues with the ignition system or fuel system. Worn-out spark plugs with carbon buildup can cause unstable ignition when the engine heats up, leading to noticeable shaking. Or if the fuel injectors are clogged, causing insufficient fuel pressure and an imbalance in the air-fuel mixture, the shaking can feel like shivering. A dirty throttle body can also affect it by making the air intake unstable. I've experienced this in my own car, and it improved significantly after replacing the spark plugs and cleaning the fuel injectors. Also, check if the engine mounts are loose—excessive vibration can cause shaking. Faulty sensors, like the oxygen sensor, can mislead the ECU. It's advisable to visit a repair shop to read the fault codes first, to avoid potential worsening problems. Regular maintenance and cleaning of these components can prevent such issues.

[McPreston]

The car shakes at idle when it's hot, and I've experienced this several times. Common causes include a dirty or clogged air filter, which restricts airflow and makes shaking more likely at high temperatures. Or there might be a small vacuum leak in the tubing, allowing air to enter and disrupt the air-fuel mixture. Low fuel pump pressure or uneven fuel injection can also cause shaking, making the engine feel like it's coughing. Cleaning the air filter once helped alleviate the issue for me. Another culprit could be excessive carbon buildup on the spark plugs, leading to unstable ignition when the engine is hot. It's advisable to inspect these basic components and maintain regular upkeep to avoid minor issues escalating into major problems. Fuel system issues like clogged injectors, especially in older models prone to buildup, might benefit from adding a fuel system cleaner. Address these promptly to prevent excessive engine strain and damage.

[VanJulia]

Engine idling vibration after warming up is something I also pay attention to while driving. It's usually related to faulty ignition coils, where spark transmission is poor and worsens at high temperatures. Or it could be due to excessive carbon buildup in the throttle body, causing issues with air intake control. If the engine mount is damaged, vibrations are directly transmitted to the car body. A simple suggestion: first, read the computer codes to identify where the fault lies. Don't let the problem persist and affect driving safety. Regular oil changes and system cleaning are key to prevention.