What Causes Idle Shuddering and Poor Acceleration?
2 Answers
Idle shuddering and poor acceleration can be attributed to the following reasons: 1. Carbon buildup: The three primary causes of insufficient car acceleration are carbon deposits on valves, idle control motors, intake passages, combustion chambers, and spark plugs, which may lead to stalling events during idle. 2. Congested road driving: Prolonged driving in heavy traffic with frequent acceleration-deceleration cycles can eventually result in a noticeable lack of power during subsequent drives. 3. Poor fuel quality: One of the most significant factors affecting acceleration performance is the use of low-quality engine oil, which can compromise gasoline filters and fuel lines, leading to inadequate fuel supply and weak acceleration.
I've driven many cars before, and the most common causes of rough idling and poor acceleration are severe engine carbon buildup. Carbon deposits can clog the intake manifold, throttle body, and fuel injectors, affecting the air-fuel mixture and leading to low combustion efficiency, which naturally results in unstable idling and weak acceleration. Additionally, worn spark plugs or faulty ignition coils can cause ignition failure. Once on the highway, my car shook violently and accelerated sluggishly; after inspection, replacing the spark plugs and cleaning the throttle body immediately improved the situation. I recommend using fuel additives regularly or performing periodic engine cleaning to prevent carbon buildup. If the steering wheel vibrates during idling, don't force it—seek professional diagnosis as soon as possible to avoid worse failures.
