What Causes Severe Vibration When Turning on the Air Conditioning in a Car?

[Micah]

The following are specific reasons for car vibration when the air conditioning is turned on: 1. Shock absorber system failure: The shock absorber system is primarily responsible for filtering engine vibrations during operation. If the shock absorbers malfunction, these vibrations will directly transmit to the steering wheel and cabin, affecting driving. When the engine is idling, turning on electrical systems inside the car can easily cause vibrations. The increased load from electrical devices causes the idle speed to drop, and to compensate for the resulting vibration, the engine automatically raises the RPM. Turning on electrical systems, especially the air conditioning, often leads to engine vibration. This vibration is likely due to aging shock absorbers and requires timely replacement. 2. Unstable oil pressure: If the engine carbon deposits have been cleaned, the throttle body washed, and the oil pads replaced, but body vibration persists, it is recommended to check the fuel supply pressure and intake pressure sensor at a repair shop. Abnormal fuel pump pressure or incorrect intake pressure sensor readings can both cause body vibration. 3. Cold start: The main reason for body vibration during a cold start is incomplete fuel combustion, resulting in insufficient power. Low ignition energy means that during startup, when fuel and lubricant temperatures are low, more throttle is needed to meet power demands. Over time, the electrode gap in spark plugs gradually widens, reducing ignition energy and impairing fuel atomization, leading to body vibration. Additionally, aging ignition coils, high-voltage wires in spark plugs, or electrical leakage can also decrease ignition energy.