What Causes Intermittent Shaking When Idling in Park?

[StVanessa]

Intermittent shaking when idling in park can be caused by: 1. Unstable oil pressure. If you've already cleaned the engine carbon deposits, throttle body, replaced oil pads and spark plugs, but the vehicle still shakes at idle, it's recommended to visit a 4S shop to check the fuel supply pressure and intake pressure sensor; 2. Aging engine components. Worn engine mounts may cause vehicle shaking. If these parts fail, the vibrations will transmit to the steering wheel and cabin; 3. Excessive dirt in the engine or carbon buildup in fuel injectors. When carbon deposits are excessive, gasoline sprayed by cold-start injectors gets largely absorbed by carbon deposits. After starting, the gasoline adsorbed on carbon deposits gets sucked into the cylinders by engine vacuum for combustion, enriching the air-fuel mixture. This results in fluctuating lean/rich combustible mixtures, causing shaking.