After the car stopped and turned off, there was a click of tiny metal in the engine compartment.

1, this sound comes from the thermal expansion and cold contraction of engine compartment components.

2. The reason for this is that when the engine is working, the temperature of the whole engine compartment is relatively high, and after the flameout, the temperature gradually decreases, which will produce this tiny contraction noise due to thermal expansion and cold contraction.

3. The temperature in some parts of the engine compartment exceeds 100℃. For example, the temperature of the whole exhaust unit is very high, and the temperature near the engine exhaust manifold is even as high as 600-800 degrees. Most of the crisp metal contraction sounds are produced on the exhaust pipe. Because this guard is used to protect non-metallic parts (cables, plastic pipes, etc. ) to avoid being damaged by contact with the exhaust pipe, this guard plate is generally suspended, and the contraction sound produced during cooling will be this very crisp metal knocking sound.

3. This sound may appear in all heated parts of the engine compartment, such as radiator, such as gearbox, and this contraction sound will disappear by itself, so there is no problem.

4. Detailed judgment can be judged by hearing aid probe. But it is usually caused by this thermal expansion and cold contraction. Don't worry.