(1) When this noise occurs, the Bare Engine can be run at idle speed and a cylinder-by-cylinder stop test is performed. Then, the throttle is shaken from idle to medium speed, and a "click" sound can be clearly heard when the throttle is shaken.

In the stop test, there is an obvious cylinder-up phenomenon, and the noise can be sensitively restored at the moment of re-firing, which can determine the noise of the large cylinder Bare Engine.

(2) During the driving of the vehicle, if the throttle is increased, a tiny "click" sound can be heard, and when the throttle is reduced or the load is reduced, the noise can be reduced or disappear, which is usually the initial sign of Bare Engine noise.

If the sound of the Mitsubishi Engine is suddenly heard during the driving of the vehicle, it seems to be the sound of drilling on hard steel parts with a large drill without lubricant. It is usually the sound of burning bearings lacking oil. When this noise occurs, the bearings may be burned and stuck.

When checking the noise of the Mitsubishi Engine, do not shake the throttle too much, and the running time of the Bare Engine should not be too long, so as not to cause a cylinder tamping accident.