What Causes the Car Engine Malfunction Light to Flash?

[Susan]

When the engine malfunction light flashes, it indicates a serious engine issue that requires immediate parking and inspection. The specific reasons may include the following seven: Sensor malfunction: The sensors referred to here include those for coolant temperature, crankshaft position, air flow, intake air temperature, oxygen sensors, etc. When these sensors are damaged, have poor connections, or experience signal interruptions, the car's ECU cannot accurately obtain engine data, which will trigger the engine malfunction light. Fuel quality issues: If fuel and engine oil are not added as required by the manufacturer, it may cause engine wear and trigger the malfunction light. Poor combustion of the air-fuel mixture: Poor combustion can lead to engine carbon deposits or knocking. When detected by the oxygen sensor and reported to the ECU, the malfunction light will illuminate as a warning. Issues such as spark plug failure, ignition coil failure, fuel pump failure, or fuel line blockage can all cause poor combustion of the air-fuel mixture. Turbocharging issues: Problems with the intake boost pipeline or turbocharger can also trigger the engine malfunction light. The most common issue is turbocharger damage, accompanied by symptoms such as oil leaks, excessive oil consumption, reduced power, metallic noises, or blue/black smoke from the exhaust. Intake issues: If there are problems with the car's intake, it may lead to engine pipeline blockages, and in severe cases, trigger the engine malfunction light. A dirty air filter that is not cleaned regularly can cause intake problems. Exhaust issues: Exhaust faults can also trigger the engine malfunction light. Common causes include rear oxygen sensor failure, catalytic converter issues, exhaust camshaft and bearing failures, with the catalytic converter being the most frequent culprit. Using leaded gasoline, lead or silicon-based lubricant additives, physical damage to the catalytic converter, or fuel system malfunctions can easily cause catalytic converter issues. Anti-theft system malfunction: If the car's electronic anti-theft system fails or the anti-theft controller does not match the engine electronic controller, the anti-theft system can prevent the engine from operating normally and trigger the malfunction light. Generally, the engine malfunction light can appear in four states: steady yellow, flashing yellow, steady red, or flashing red. The severity of the issue increases from steady to flashing and from yellow to red. In order of severity: flashing red > flashing yellow > steady red > steady yellow. If the engine malfunction light comes on, follow these steps: First, check if the engine is running normally, whether there is shaking, black smoke, etc. If so, avoid restarting the engine. Note: Do not restart the engine if the red light is on. If the engine can start, turn it off for 5-10 minutes, then without pressing the brake, press the start button once or turn the key halfway to the "on" position without pressing the clutch. The car will perform a self-check after powering on. Wait 5-10 seconds to see if the malfunction light turns off. If the light remains on, visit a service station as soon as possible. The service station can use a portable diagnostic tool to read the fault code, identify the issue, and perform targeted repairs.