What are the causes of the malfunction indicator light turning on?
2 Answers
Engine malfunction indicator light stays on for the following reasons: 1. Poor quality gasoline that fails to meet standards: Leads to incomplete combustion of the air-fuel mixture in the cylinders, producing excessive carbon deposits, which directly affects the normal concentration of the air-fuel mixture, causing the engine malfunction light to illuminate accompanied by shaking. 2. Damaged oxygen sensor: A faulty oxygen sensor or sensor connector can cause the air-fuel mixture to become too lean or too rich, triggering the malfunction light. 3. Circuit faults: Malfunctions in the mass air flow sensor or its circuit prevent the engine control unit from receiving accurate intake air volume signals, making it unable to properly control the fuel injection quantity, resulting in either too lean or too rich air-fuel mixture, engine operation failure, and continuous illumination of the malfunction indicator light.
I've been driving for over ten years and have encountered the check engine light coming on several times. Common causes include sensor issues like a faulty oxygen sensor, which might falsely indicate excessive emissions; vacuum hose leaks or loose electrical connectors causing system abnormalities; or a dirty mass airflow sensor giving inaccurate readings that trigger the light. Also, using low-quality fuel resulting in unqualified exhaust emissions can illuminate the light. I remember last time my light came on due to a minor issue I ignored, which almost led to major problems. So never delay - promptly visit an authorized repair shop to scan for trouble codes with a diagnostic scanner, as this is the only way to accurately identify and fix the problem. Safe driving comes first - that illuminated light could indicate engine or other critical component issues. Never assume it will turn off by itself.
