What Causes Severe Engine Vibration When the Car Air Conditioner is On?
2 Answers
Carbon buildup on spark plugs, carbon deposits in the throttle body, or deformed fans and loose screws can all cause engine vibration when the car air conditioner is on. Specific reasons are as follows: 1. Throttle body malfunction: When the throttle body fails, the vehicle may exhibit symptoms such as engine vibration, unstable idling, weak acceleration, and difficulty starting when cold. In this case, the throttle body should be thoroughly cleaned, especially removing any oil sludge attached to it. If the throttle body is structurally damaged, it should be replaced promptly. 2. Throttle position sensor issues: When the throttle pedal malfunctions, the vehicle may show symptoms like weak acceleration, severe jerking, or unresponsiveness to throttle input. In such cases, the throttle position sensor should be inspected, and it's advisable to use high-quality fuel regularly. After repairs, ensure to clear any fault codes promptly; otherwise, it may cause memory confusion in the vehicle's electronic system, leading to unnecessary issues later on.
Severe engine shaking when the air conditioning is on mainly occurs because turning on the AC increases the engine's load, as the compressor consumes more power. Having driven many older cars, I've often found that the issue stems from aging engine components, such as problems with spark plugs or ignition coils. Once the load increases, the ignition efficiency drops, making engine speed fluctuations more noticeable. Other factors include faults in the idle control system or carbon buildup clogging the fuel system, leading to uneven fuel combustion. If these issues are overlooked during regular maintenance, the shaking becomes more pronounced when the AC is turned on, especially noticeable when idling at traffic lights. It's advisable to start with simple checks, like replacing the spark plugs, to see if the shaking reduces. Neglecting repairs for too long may affect the engine's lifespan or even lead to a breakdown, particularly during long summer trips. In short, it's not just a minor issue but could hide major risks, so it's best to consult a professional technician as soon as possible.
