What Causes the Buick Excelle to Shake on Startup and Have Weak Acceleration?
3 Answers
Buick Excelle shaking on startup and having weak acceleration can be attributed to the following reasons: 1. Severe engine carbon buildup: The most common cause of car shaking is a dirty throttle body or excessive carbon deposits in the fuel injectors. When there is too much carbon buildup inside the engine, the gasoline sprayed by the cold-start injector can be largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts and making it difficult to start. The solution is to clean the fuel system and check if the idle control valve has carbon buildup, which should also be cleaned. 2. Ignition system issues: Check the condition of the spark plugs, high-voltage wires, and ignition coils. Poor performance of the ignition system or weak spark plug firing can also lead to such symptoms. The solution is to inspect whether the spark plugs have excessive carbon buildup and replace them if necessary. 3. Unstable fuel pressure: If you have already cleaned the engine carbon deposits, cleaned the throttle body, replaced the fuel filter, and spark plugs but still notice the car shaking at idle, it is recommended to visit a 4S shop to check the fuel supply pressure and the intake pressure sensor. Abnormal fuel pump pressure or incorrect readings and poor performance of the intake pressure sensor can cause the car to shake. The solution is to check the fuel pressure and replace components if necessary. 4. Aging engine components: Car shaking can also be related to worn engine mounts. Engine mounts act as the shock absorption system for the engine, absorbing minor vibrations during operation. If the engine mounts are faulty, these vibrations can be transmitted to the steering wheel and the cabin, causing shaking at idle.
The Buick Excelle experiences shaking during startup and lacks power during acceleration, both of which are quite common issues. I think it's worth starting with the ignition system. If the ignition coil is aged or damaged, causing misfires, the car will shake like it's dancing during startup. If the spark plugs haven't been replaced for a long time and have excessive carbon buildup, ignition delay occurs, making acceleration feel sluggish. Additionally, a clogged air filter restricts airflow, leading to incomplete fuel combustion, which worsens the shaking and power loss. Don’t forget to check for dirt or carbon buildup in the throttle body, as this can slow down engine response. I suggest doing a simple self-check first, such as removing the spark plugs to see if they’re blackened and trying new ones. However, if the shaking is severe, it might be due to loose engine mounts—it’s best to visit a repair shop for diagnosis to avoid hidden risks. Don’t slack on car maintenance.
When it comes to the reasons for the Buick Excelle shaking and lacking power, I suspect it's an ignition or fuel issue. When spark plugs or ignition coils fail, cylinder misfires cause tremors during startup; when fuel injectors are clogged with carbon deposits, insufficient fuel supply makes acceleration feel like stepping on cotton. The intake system is also crucial—a clogged air filter reduces airflow, lowering combustion efficiency. Additionally, poor fuel quality leads to excessive engine carbon buildup, reducing power output, or insufficient fuel pump pressure affecting acceleration. You can try cleaning the throttle body or replacing the filter yourself, but use a tool to scan OBD codes to pinpoint the fault. Repairing early saves money and ensures safety—don’t delay too long.
