Fault-free display of instrument for insufficient power of Dongfeng Renault 420 black smoke engine

The lack of engine power and poor acceleration are generally caused by low fuel pressure, poor fuel injection by injector, low ignition pressure or energy, incorrect ignition timing, low cylinder compression pressure and blocked exhaust pipe. In general, the following methods can be used to check and determine the specific cause of the fault:

1. Press the accelerator pedal to the bottom and check whether the throttle valve can be fully opened. If it cannot be fully opened, adjust the accelerator cable or pedal. 2. Check whether the air intake system is blocked or leaked. If the intake system is blocked or leaked, it will inevitably affect the charging efficiency of the engine, resulting in the decline of engine power and acceleration performance. Specifically, it is to check whether the air filter, air inlet pipeline and various vacuum hoses are blocked or leaked.

3. Check whether the exhaust system is blocked. The back pressure of the exhaust system is generally controlled within 2.5 atmospheres. If the back pressure of the exhaust system is too high due to the blockage of the exhaust pipe, it will inevitably lead to the increase of the residual exhaust gas content in the cylinder, which will lead to the decrease of the combustion speed of the mixed gas and the effective pressure of the cylinder. The main reasons for the increase of back pressure in exhaust system are the blockage of exhaust pipe, the deformation of exhaust muffler or three-way catalytic converter, etc. These parts should be inspected.

4, check whether the fuel system oil supply is normal. ① Check the pressure of the fuel system. If the pressure of the fuel system is abnormal, especially when the pressure of the fuel system is too low, the fuel injection quantity of the fuel injector will be reduced per unit time, which will cause the mixture to be too lean and the power performance of the engine will be greatly reduced, resulting in insufficient engine power and poor acceleration.