1. The engine lacks a cylinder, a cylinder misfire does not work, and the spark plug or ignition coil in a certain cylinder does not work. Use the method of elimination to find out which cylinder is faulty. For example, pull out the coils of one cylinder in turn. If the shaking of the car is seriously intensified, it means that there is no problem with this cylinder; if the shaking of the car does not change much, it means that there is a problem with this cylinder, and then check whether the ignition coil and ignition coil rails in this cylinder are damage.
2. The low-voltage plug is in poor contact with the wiring harness, it is connected and sometimes it is not connected, resulting in the engine sometimes lacking cylinders and sometimes normal. For this phenomenon, fix the low-voltage plug with a cable tie or replace it with a new plug.
3. The power cord connecting the ignition coil is broken, and the damaged part is in contact with the engine casing, causing the ignition coil to lack a cylinder and the car to shake. When the car shakes, due to the vibration, the wiring harness jumps out of the engine casing again. At this time, the input current returns to normal, and the ignition coil works normally again. This phenomenon of on-off and on-off (of course, the frequency of change is very fast) makes the car shake and frustrated the car. Over time, it will affect the life of the ignition coil and even damage the coil.
4. The parameter design of the ignition coil in general factories is unreasonable, and the output voltage and output energy of the coil are too low. The spark plug cannot be ignited normally or the ignition effect is low. In this way, the car will vibrate and frustrate the car. It is recommended to replace it with an original or genuine ignition coil product.