What Causes the Yellow Engine Light to Illuminate in a Haval?

[McAngela]

Here are the specific reasons why the yellow engine light illuminates in a Haval: Abnormal Fuel Pressure: If the fuel pump's supply pressure fails to reach the required level, it can result in poor atomization of the fuel injectors, thereby affecting the engine's normal operation. Normally, the fuel pump pressure should be between 2.5—3.5 MPa. If the fuel pump pressure exceeds 3.5 MPa, the injector spring may struggle to overcome the fuel pressure after the injector operates, leading to continuous fuel injection and causing excessively rich exhaust emissions. Engine Knock or Detonation: The engine is equipped with a dedicated knock sensor to monitor engine knock. Engine knock can potentially cause severe mechanical damage or significant power loss. Typically, knock is categorized into perceptible and imperceptible knock. In cases of imperceptible knock, the engine control unit (ECU) adjusts engine control parameters based on the monitored conditions to prevent further adverse effects. However, when imperceptible knock exceeds the adjustable range of the ECU, the engine fault light will also illuminate as a warning.