(1) air supply system.

Air intake system is an important part of electronically controlled fuel injection system. Faults that lead to inaccurate gas supply mainly include:

1, the leakage of intake pipe and various valves, the common ones are the broken intake manifold, poor seal of intake manifold, vacuum tube falling off, and the PCV valve /EGR valve not being closed properly. For example, under normal circumstances, the opening of the idle speed control engine and the air intake should strictly follow a certain functional relationship, that is, the air intake will increase when the idle valve is opened. When the air supply system leaks, the air intake and the opening of the idle speed control valve can't follow the original functional relationship, which makes the air flowmeter unable to accurately measure the real air intake, resulting in inaccurate near-intake signals obtained by the engine electronic control unit (ECU), which leads to misjudgment and unstable idle speed of the engine.