Huanghai Jinma 504 can't get off at idle speed

Fuel injection is excessive. The reason why Huanghai Jinma 504 can't idle down is that there is too much fuel injection, too much air intake at idle speed and the engine control signal is wrong. The solutions to high idle speed are to adjust or replace the throttle position sensor, clean or replace the idle speed control valve, use the decoder to basically set the idle speed, find the leakage, reseal or replace the relevant parts, check the timing mark, readjust the valve timing according to the standard, clean and check the injection quantity of each injector to ensure no blockage and leakage, and replace the three-way catalytic converter to eliminate egr.