What Causes the Engine Malfunction Light to Illuminate on the Dashboard?

[SanJessica]

The illumination of the engine malfunction light on the dashboard indicates a fault in the vehicle's engine. Possible causes for the engine malfunction light include turbocharging issues, substandard exhaust emissions, clogged fuel injectors, throttle position sensor problems, and in some vehicles, transmission system faults that are also indicated via the engine malfunction light. Specific causes are detailed below: Sensor Issues: Sensors such as coolant temperature, crankshaft position, air flow, intake temperature, and oxygen sensors can trigger the engine malfunction light when they are damaged, have poor connections, or experience signal interruptions. This prevents the vehicle's ECU from accurately obtaining engine data. Turbocharging Issues: Problems with the intake turbocharging pipeline or turbocharger can also cause the engine malfunction light to illuminate. The most common issue is a damaged turbocharger, often accompanied by symptoms such as oil leaks, excessive oil consumption, reduced power, metallic noises, or blue/black smoke from the exhaust. Exhaust Issues: Faults in components like the rear oxygen sensor, catalytic converter, exhaust camshaft, and bearings can lead to the engine malfunction light turning on. The most frequent cause is a faulty catalytic converter, which can result from using leaded gasoline, lead- or silicon-based lubricant additives, physical damage to the catalytic converter, or issues with the engine's fuel supply system. Anti-Theft System: If the vehicle's electronic anti-theft system malfunctions or if the anti-theft controller does not match the engine's electronic controller, the anti-theft system can prevent the engine from operating normally and trigger the engine malfunction light. Precautions: If this fault occurs, the vehicle should not be driven. It is necessary to check whether the coolant level is low, whether the engine oil requires replacement or is insufficient, clean the throttle body and intake passages, inspect the spark plugs for proper function, and verify the condition of the ignition coils. The vehicle should not be driven until these checks are completed.