What Causes the Engine Light to Illuminate in a Car?

1 Answers
OGeorge
07/29/25 7:31am
There are several reasons why a car's engine warning light may illuminate, including sensor malfunctions, maintenance issues, and fuel/oil quality problems. Sensor malfunctions: Sensors such as coolant temperature, crankshaft position, air flow, intake air temperature, and oxygen sensors can trigger the engine light when damaged, experiencing poor contact, or signal interruption. In such cases, the vehicle's ECU cannot accurately obtain engine data. Maintenance issues: Poor engine maintenance is the most common cause of engine warning light activation. Vehicles have specific maintenance schedules, and failure to adhere to these schedules combined with poor driving habits can increase the engine's operational burden, eventually triggering the warning light. Fuel/oil quality problems: This refers to both fuel and engine oil quality. Automobiles typically require specific fuel grades, while engine oils are categorized as semi-synthetic or fully synthetic. Manufacturers usually recommend appropriate fuel grades and oil types. Failure to follow these recommendations over time can lead to engine wear.
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