What Causes Car Vibration When the Air Conditioner is On?

[Aniyah]

Here are the reasons for car vibration when driving: 1. Spark plugs with carbon deposits: After a period of use, spark plugs can accumulate carbon deposits. If not cleaned in time, this can reduce the engine's torque output, causing vibration when the air conditioner is on. 2. Abnormal cylinder pressure: Generally, older cars have a normal cylinder pressure of around 10.5, while newer cars have pressures of 11 or more. If the cylinder pressure is abnormal, the car's computer will detect cylinder misfire and automatically cut off fuel supply, leading to vibration when starting the car until it fails to start. 3. Poor fuel quality: The fuel octane number represents the fuel's anti-knock index. Higher-grade fuel can extend the lifespan of the three-way catalytic converter and reduce emissions. Additionally, engines with different compression ratios require different fuel qualities. Using the wrong gasoline can cause severe engine carbon deposits, resulting in car vibration when the air conditioner is on.