Golf 1.4T What happened when I felt the car shake at idle speed?

The reason of vehicle idling jitter may be: 1. Dirty throttle will cause idling jitter. 2. Spark plug failure will lead to vehicle idling jitter. 3. Engine cylinder 1 does not work, which will also lead to idle jitter. There will also be vehicle jitter when the vehicle accelerates at low speed. 4. The rubber parts inside the engine bracket and the gearbox bracket are aging, which leads to vehicle idling jitter.