What to Do When the Engine Malfunction Light Comes On After Refueling?
1 Answers
If the engine malfunction light comes on after refueling, it indicates that poor-quality fuel has been added. During the combustion process in the engine, due to the high impurity content and low combustion efficiency of poor-quality fuel, some impurities and unburned fuel accumulate in the combustion chamber, occupying space and subsequently causing the engine malfunction light to illuminate. Solution: Promptly drain the poor-quality fuel and clean the fuel tank and fuel lines. After cleaning, replace with high-quality fuel. Apart from fuel quality issues, the following reasons can also cause the engine malfunction light to come on: Sensor Malfunction: The sensors mentioned here include coolant temperature, crankshaft position, air flow, intake air temperature, oxygen sensors, etc. When these sensors are damaged, have poor contact, or their signals are interrupted, the vehicle's ECU cannot accurately obtain engine data, leading to the illumination of the engine malfunction light. Poor Combustion of Air-Fuel Mixture: Poor combustion of the air-fuel mixture can cause engine carbon buildup or knocking. When detected by the oxygen sensor and reported to the ECU, the malfunction light will illuminate as a warning. Issues such as faulty spark plugs, ignition coils, fuel pumps, or clogged fuel lines can all lead to poor combustion of the air-fuel mixture. Turbocharging Issues: Problems with the intake boost piping or turbocharger can also cause the engine malfunction light to come on. The most common issue is a damaged turbocharger, 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 vehicle's intake system, it may lead to engine pipe blockages, and in severe cases, cause the engine malfunction light to illuminate. A dirty or uncleaned air filter can result in intake problems. Exhaust Issues: Exhaust system faults can also trigger the engine malfunction light. Common causes include faulty rear oxygen sensors, catalytic converters, exhaust camshafts, or bearings, with the catalytic converter being the most frequent issue. Using leaded gasoline, lead- or silicon-containing lubricant additives, physical damage to the catalytic converter, or fuel system malfunctions can easily lead to catalytic converter failure. Anti-Theft System Malfunction: If the vehicle's electronic anti-theft system fails or if the anti-theft controller does not match the engine electronic controller, the anti-theft system can prevent the engine from operating normally, and the engine malfunction light will illuminate.
