1. The throttle is unstable:
The unstable idle speed of the excavator is generally caused by the mixture of too rich or too lean, incomplete ignition or incorrect sensor signals of the excavator accessories.
1. Check the pressure of each cylinder, if the cylinder pressure is uneven, it will cause unstable idle speed.
2. Check whether the fuel pressure is stable, whether the fuel injection volume of the fuel injector of the excavator accessories is consistent, and the damage of the fuel injector (if there is no blockage or leakage, etc.).
3. Check the booster pressure sensor of excavator accessories. If the boost pressure sensor fails, it will not be able to feed back a normal signal to the engine ECU, and it will not be able to correct the fuel injection amount. When idling, the engine will be supplied with too rich or too lean mixture, causing idling instability.
Second, the throttle does not respond:
1. First, manually add the fuel valve. If the manual oil pump can be accelerated, the problem of the hand oil pump can be eliminated.
Excavator accessories hand oil pump
2. Check whether the oil circuit is blocked and whether the diesel filter is blocked or dirty. If there is no abnormality in the above, it is necessary to consider whether the high-pressure common rail is faulty.
3. You can check whether the throttle motor circuit of the excavator accessories is broken or the motor itself is faulty.
3. Always in a state of high throttle:
When the excavator is started, the throttle is high. When the throttle is lowered, the engine speed still does not drop. The possible reason is that the low-pressure sensor of a certain excavator accessory works abnormally, causing the program to incorrectly judge that the machine is in working state, so there will be a high throttle when it starts. The phenomenon. In addition, if there is no change in the speed after the accelerator is lowered, it may be that the speed sensor is abnormal.
Fourth, the engine throttle is abnormal:
Abnormal engine throttle is very important to the operation of the excavator. If the throttle is abnormal, it will not only affect the work efficiency, but also cause the flameout phenomenon in serious cases. Generally speaking, there are three main cases of abnormal throttle of excavator accessories in Jiangsu.
