Why does the Buick Excelle idle speed fluctuate unstably?
1 Answers
Buick Excelle idle speed fluctuation reasons are as follows: Throttle body oil accumulation and carbon deposits, dirty intake manifold: Blockage in the intake manifold can cause idle speed fluctuations, while carbon deposits or oil accumulation in the throttle body are the most common causes of unstable idle speed. Carbon deposits in the throttle body can affect its opening degree and air intake volume, causing the engine speed to fluctuate significantly after a cold start, accompanied by strong vibrations. Severe oil accumulation or carbon deposits in the throttle body, including a dirty intake manifold, can make the car difficult to start in cold weather. Cleaning the throttle body is necessary, and it is considered a routine maintenance task. Weak spark caused by faulty spark plugs: Spark plugs can also accumulate carbon deposits, which can be cleaned to restore their activity. However, some spark plugs may be nearing the end of their lifespan, leading to reduced performance. Weak sparks from individual spark plugs can affect the car's performance. Faulty spark plugs can cause "misfire" symptoms, but minor faults in individual spark plugs may result in unstable idle speed. Therefore, when the car experiences unstable idle speed, cleaning or replacing the spark plugs is also a viable solution.
