What Causes Significant Body Vibration When the Air Conditioning is Turned On in a Buick Excelle?
2 Answers
Excessive carbon deposits in the engine, a dirty throttle, excessively high compressor pressure, and a small car displacement can all lead to noticeable body vibration when the air conditioning is turned on in a Buick Excelle. Excessive carbon deposits in the engine: When there is too much carbon buildup inside the engine, the gasoline sprayed by the fuel injector during a cold start can be absorbed by these deposits, causing body vibration after the air conditioning is turned on. Cleaning the internal carbon deposits in the engine can help. If a large amount of carbon buildup is noticed in a very short period, it is essential to have the vehicle inspected at a 4S shop immediately. In case the excessive carbon deposits are due to faulty components, timely repairs or replacements can prevent the situation from worsening. Dirty throttle: A dirty throttle can affect engine performance. Turning on the air conditioning in this condition can worsen engine idling, leading to steering wheel vibration. Therefore, cleaning the throttle can prevent this issue. Excessively high compressor pressure: If idling vibration occurs immediately after turning on the air conditioning, it may be due to issues with high and low pressure. It is crucial to check the air conditioning's high and low pressure to see if the pressure is too high. Excessive pressure increases the engine load, affecting the car's stability. For this situation, it is advisable to visit a repair shop for further inspection and timely resolution. Small car displacement: Small-displacement cars are more significantly affected by the air conditioning, leading to more noticeable vibration. This is particularly evident in cars with displacements below 1.5L. Therefore, noticeable body vibration when the air conditioning is turned on due to this reason is considered normal. A 1.5L engine typically has a maximum power output of around 80 kW, while the air conditioning compressor consumes about 2 kW. At idle, the engine's power output is only around 10 kW, making the compressor's power consumption proportionally significant. Suddenly applying a large load to the engine can make it harder for the engine to rotate smoothly, resulting in noticeable vibration. However, once the car starts moving and the engine speed increases, the engine's power output rises, reducing the proportion of power consumed by the compressor, and the vibration diminishes.
I also experienced body shaking when driving my Buick Excelle with the AC on, feeling like the engine was working extra hard. The engine load increases significantly when the AC is running, especially noticeable during idle at traffic lights. The main reasons could be aging or cracked engine mount rubber, reducing vibration absorption; or issues with the ignition system, such as carbon buildup on spark plugs causing unstable operation; or the AC compressor starting too aggressively, overwhelming the engine. For a quick self-check: listen for unusual engine sounds and check if the RPM is stable when starting the car. If the shaking is severe, visit a professional repair shop promptly—replacing parts isn't expensive, but don't delay, as prolonged shaking can damage internal components, affecting safety and driving comfort. During regular maintenance, have the mechanic inspect the mounts and ignition system to prevent future issues.
