What Causes Severe Vibration When the Air Conditioning is Turned On in a Buick Excelle?

[LeHailey]

Buick Excelle experiences severe vibration when the air conditioning is turned on due to a dirty throttle body and insufficient engine power. Insufficient engine power: When the engine power is low, high idle speed indicates that the compressor is working. When the compressor is not operating, the idle speed drops, and the steering wheel does not vibrate. When the air conditioning is turned on during normal driving, the increased load from the compressor causes the engine speed to decrease, resulting in noticeable vehicle vibration. To address this issue, manufacturers typically install an engine idle speed boost system for air conditioning. This system increases the engine speed to the required range when the air conditioning compressor is active. Dirty throttle body: A dirty throttle body affects engine performance. Turning on the air conditioning under these conditions further increases the engine idle load, leading to steering wheel vibration. Cleaning the throttle body can prevent this issue. The vibration caused by air conditioning use, based on current vehicle conditions, is likely due to a dirty throttle body. It is recommended to have it cleaned at a repair shop. According to current vehicle control technology and maintenance cases, this is a common issue. Throttle carbon buildup is primarily caused by the engine control unit's characteristics, as well as factors such as low temperatures, low-speed driving, short-distance trips, and frequent starts. The noise from the air conditioning system is normal compressor operation, and no other issues are likely present. The engine drives the air conditioning compressor to provide cooling, which is a heavy load for the engine. When the air conditioning is turned on, the engine must also power the compressor, leading to noticeable power loss and increased vibration. This effect is more pronounced at idle speed. Increasing the idle speed slightly may improve the situation, though it will result in higher fuel consumption.

[VanEmersyn]

I used to drive an old Buick Excelle, and the car would shake badly when the AC was turned on, especially noticeable at idle. The core issue is often that the AC compressor starting up increases the engine load, and as a result, the engine mounts become aged and loose, transmitting vibrations throughout the body. My Excelle had worn-out mounts, and replacing them made a big difference. It's also necessary to check the ignition system, as worn-out spark plugs or ignition coils can cause shaking; or if the throttle body is too carbon-fouled, it can affect air intake and make the engine unstable. A clogged air filter can also worsen the problem, so I often recommend regular cleaning and maintenance. While this kind of shaking is common, it can make driving uncomfortable and even wear out other components. For safety's sake, it's best to head to the repair shop for a full check-up—it's not expensive but can prevent major headaches.

[DeLaura]

Having worked on car repairs for many years, I've dealt with numerous cases of Buick Excelle shaking when the AC is turned on. The causes are usually multifaceted: the sudden increase in load after the AC compressor kicks in can transmit vibrations if the engine mounts are damaged; minor issues in the ignition system, such as excessive spark plug gaps or aging ignition wires, can also cause engine misfires, which become apparent when the AC is turned on; a dirty throttle body or a clogged air filter can lead to unstable operation due to restricted airflow. Electrical system problems, like unstable alternator voltage, can also contribute to the issue. Start with simple checks—inspect the mounts for damage and try replacing the spark plugs yourself; if that doesn't help, it's best to consult a professional technician with a diagnostic tool. Ignoring such problems can lead to more severe engine damage, which is not worth the risk.

[VanZoe]

My Buick Excelle shakes badly when the AC is turned on. After checking, I found common causes include worn-out engine mounts, the compressor's startup load being too heavy to handle, or spark plugs needing replacement leading to unstable ignition. Another possibility is excessive carbon buildup in the throttle body causing insufficient air intake. In my case, it was carbon deposits causing the trouble - cleaning them improved things significantly. Don't slack on regular maintenance; periodic upkeep can prevent issues, like cleaning the throttle body or checking the air filter. Severe shaking makes driving uncomfortable, wastes fuel, and affects safety - address it promptly. Simple repairs don't cost much, so don't delay until small problems become big ones.