What will happen if the engine of a hot car is shaking and there is no cylinder shortage?

1. The most common thing is that the throttle is dirty or the throttle fails, which will lead to idle jitter. The main reason of dirty throttle is that there is carbon deposit at the joint between throttle valve plate shaft and throttle body, which leads to inaccurate throttle opening, so the idle speed will shake. So we can clean the throttle first. If it doesn't shake after cleaning, it means the throttle is dirty. If it still shakes after cleaning, it may be that the throttle assembly is damaged and the throttle needs to be replaced. Just a reminder, because all vehicles use electronic throttle now, you need to learn idle again after cleaning the throttle.

2. Poor gasoline quality leads to poor atomization effect of fuel injector, and insufficient combustion of mixed gas in cylinder will also lead to idling jitter. It is recommended to use high-grade gasoline after using this box of gasoline and do a fuel system cleaning.

3. The spark plug does not ignite, resulting in one or more cylinders not working, which will also lead to idle jitter. Check the spark plug. If there is a crack in the ceramic part of the spark plug, it is necessary to check whether the ignition module is normal.