What Causes a Small Car to Display an Engine Fault?

[LoganRose]

The reasons why a small car displays an engine fault: 1. Sensor issues: The sensors mentioned here include water temperature, crankshaft position, air flow, intake temperature, oxygen sensors, etc. When these sensors are damaged, have poor contact, or signal interruption, the car's ECU cannot accurately obtain engine data, which will cause the engine fault light to illuminate. 2. Fuel quality issues: Fuel quality includes both fuel and engine oil. The fuel added to a car generally has a specific grade, and engine oil can be semi-synthetic or fully synthetic. Manufacturers usually recommend that owners use the specified fuel and engine oil. If the owner does not add them as required, long-term use will cause engine wear. 3. Poor combustion of the air-fuel mixture: Faults in the engine's spark plugs, ignition coils, fuel pump, or clogged fuel lines can all lead to poor combustion of the air-fuel mixture. Poor combustion of the air-fuel mixture results in engine carbon deposits or knocking problems. When the engine's oxygen sensor detects the issue and reports it to the ECU, the fault light will illuminate as a warning.