What to Do When the Engine Malfunction Light Turns Yellow

2 Answers
VonJoel
07/24/25 4:42am
When the yellow light on the dashboard illuminates during vehicle use, it indicates that the vehicle's engine requires maintenance and servicing. Below is relevant information about the engine malfunction light: 1. Reasons for the Light: The engine malfunction light (referred to as the MIL light) turns on due to a fault in components monitoring vehicle exhaust emissions. The onboard diagnostic system (OBD) detects excessive exhaust emissions, such as issues with the ignition coil, spark plugs, catalytic converter, exhaust valve, fuel injector, intake pressure sensor, oxygen sensor, etc. 2. Consequences of the Light: When the engine malfunction light is on, the engine may operate abnormally. If not addressed promptly, it can lead to problems such as increased combustion chamber temperature and accelerated wear, potentially causing premature engine damage. Additionally, engine noise may increase, affecting driving and passenger comfort. Fuel consumption may also rise, wasting petroleum and financial resources. The engine may start burning oil.
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Rhonda
08/11/25 12:21am
Last time the engine warning light in my car also lit up yellow, which scared me so much that I immediately pulled over to check. I looked it up and generally, it's due to issues with the emission system, like a faulty oxygen sensor or a clogged exhaust. I tried restarting the engine to see if the light would go off, but it didn't work, so I had to drive to the repair shop. The mechanic said the yellow light indicates it's not an urgent failure and the car is still drivable, but it needs to be addressed as soon as possible. He also reminded me to pay attention to fuel system maintenance and avoid using low-quality fuel, otherwise the sensors could get damaged. Later, the diagnosis showed it was an oxygen sensor failure, and replacing the part cost me over 300 yuan. In short, don't panic in such situations—safety first, reduce speed to under 60, and seek professional repair immediately.
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