1. Vacuum Leak: A vacuum leak can cause rough idling and shaking, and pressing the accelerator can temporarily stabilize it. Check for any loose or damaged vacuum hoses.
2. Fuel System Issues: A clogged or dirty fuel filter, faulty fuel injector, or a problem with the fuel pump can lead to poor fuel delivery, resulting in rough idling and stalling.
3. Idle Air Control (IAC) Valve: The IAC valve regulates the airflow to maintain the engine's idle speed. A faulty or dirty IAC valve can cause erratic idle behavior.
4. Faulty Ignition System: Issues with spark plugs, ignition coils, or high-voltage wires can cause engine misfires and rough idling. Check for worn or damaged components.
5. Oxygen Sensor: A malfunctioning oxygen sensor can affect the fuel-to-air mixture, leading to rough idling and shaking.
6. Engine Mounts: Worn or damaged engine mounts can allow excessive engine movement, causing shaking and vibration.
7. Faulty Engine Sensors: Other sensors, such as the mass air flow (MAF) sensor, coolant temperature sensor, and throttle position sensor, can affect idling stability.
Solution:
To diagnose and fix this problem, it is recommended to have a professional mechanic inspect the vehicle and identify the specific cause. They can perform diagnostic tests, inspect the necessary components, and make any necessary repairs or replacements to ensure smooth engine operation and stability.
