What Causes Vibration in the Accelerator Pedal at 100 km/h on the Highway?
2 Answers
There are three possible conditions for the vehicle: 1. Severe engine carbon buildup: The most common cause of car vibration is a dirty throttle body or excessive carbon deposits in the fuel injectors. When there is too much carbon buildup inside the engine, the gasoline sprayed by the cold-start injector can be largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts and making it difficult to start. 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 sparking from the spark plugs can also lead to such faults. 3. Unstable fuel pressure: If you have already cleaned the engine carbon deposits, cleaned the throttle body, replaced the oil seals and spark plugs, but still notice body vibration at idle, it is recommended to visit a 4S shop to check whether the fuel supply pressure and intake pressure sensors are functioning properly. Abnormal fuel pump pressure or incorrect readings and poor performance of the intake pressure sensor can cause body vibration. 4. Aging engine components: Car vibration can also be related to aging engine mounts (also known as engine mounts). Engine mounts are essentially the shock absorption system for the engine, responsible for absorbing minor vibrations during operation. If the engine mounts are faulty, these vibrations can be transmitted to the steering wheel and the cabin, causing vibrations at idle.
Last time I was driving on the highway at around 100 km/h, the accelerator pedal started vibrating, and the sensation was particularly noticeable under my feet. A common cause of this vibration is tire imbalance, which leads to uneven rotation of the wheels. When a wheel spins, if there is an imbalance in weight distribution, it creates periodic shaking. The vibration is transmitted through the car body to the accelerator pedal. Tire deformation or a damaged wheel hub can also cause this. It’s important to get a tire balance done as soon as possible, as prolonged vibration can damage the suspension system. Additionally, misaligned wheel alignment or uneven tire pressure can worsen the vibration. I recommend visiting a reputable tire shop for an inspection—spending around 100 RMB on a balance should resolve the issue.
