What Causes Engine Stalling and Shaking at Idle?
2 Answers
The reasons for engine stalling and shaking at idle are: 1. Throttle valve clogging, carbon buildup, or abnormal opening; 2. Fuel injector carbon buildup or clogging; 3. Spark plug burning or damage; 4. Use of low-quality gasoline leading to fuel pump blockage; 5. Incomplete combustion of air-fuel mixture in the cylinder. When the engine starts and runs well from low to high speeds but stalls immediately after releasing the accelerator pedal or becomes unstable before stalling, this can be identified as an idle stalling fault. Solutions for vehicle idle shaking and stalling include: 1. Regularly clean the throttle valve; 2. Periodically clean fuel injectors to prevent carbon buildup; 3. Replace spark plugs; 4. Use gasoline from authorized gas stations.
I previously encountered an issue where my car would shake and stall at idle. At first, I thought it was a minor problem, but later discovered it was caused by worn-out spark plugs. Over time, spark plugs accumulate carbon deposits, and the electrode gap widens, leading to unstable ignition. This causes the engine to surge and shake at idle, and in severe cases, it can stall completely. I also suspected a faulty ignition coil, which supplies power to the spark plugs. If the voltage is unstable, the spark can become intermittent. Additionally, a clogged air filter can restrict airflow, disrupting the air-fuel mixture and making the engine struggle. The best solution is to first replace the spark plugs and then check the ignition coil and air filter. If left untreated, the shaking could worsen during your next drive, and you might even experience sudden loss of power at high speeds, which is extremely dangerous. I recommend replacing spark plugs every 20,000 kilometers as part of regular maintenance—don’t skimp on this small expense.
