If your vehicle is showing vibration in the steering wheel while idling, here are the most likely causes and the parts you'll need to fix each one.
The rubber isolators in the mounts degrade, collapse, or tear over time. This allows normal engine vibrations to transfer directly into the vehicle's chassis and steering column.
Worn spark plugs, failing ignition coils, or vacuum leaks cause the engine to run unevenly. This imbalance creates a shaking sensation that is easily felt through the steering wheel at a stop.
Carbon buildup in the throttle body or a sluggish idle air control valve causes the engine idle RPM to drop too low, making the engine lug and vibrate heavily.
If motor mounts were recently replaced and fully tightened before the engine's weight was allowed to settle naturally, they can bind and transfer excessive vibration to the chassis.
A failing A/C compressor can create excessive mechanical drag on the engine when the clutch engages, dropping the idle speed and causing a noticeable vibration.
The rubber dampener on the engine's main crankshaft pulley can deteriorate and separate. This causes the heavy pulley to wobble, sending severe vibrations through the engine block.