What Causes the Engine Fault Indicator to Illuminate on the Car Dashboard?
3 Answers
Reasons why the car dashboard displays an engine fault: 1. Lack of regular maintenance—approximately 50% of engine faults are caused by poor maintenance; 2. Degraded engine oil; 3. Clogged air filter; 4. Dirty intake pipes, leading to reduced charging efficiency, which prevents the engine from operating within the normal power range and accelerates wear and aging; 5. Excessive sludge in the crankcase—small amounts can remain suspended in the oil, but large quantities may separate, clogging filters and oil passages, making lubrication difficult and worsening engine wear; 6. Gum deposits and carbon buildup in the fuel system; 7. Rust and scale in the radiator.
Last time I encountered a pretty typical case when repairing a car - the owner of that Tiguan suddenly had the engine warning light come on. When this light illuminates, it's essentially the onboard computer protesting, having detected abnormal engine operating parameters. The most common scenarios are sensor malfunctions, like an oxygen sensor giving false readings due to carbon buildup, or a failing intake pressure sensor. Even a loose fuel cap can trigger it, as fuel vapor leakage may cause system misjudgment. Of course, mechanical failures like misfires from worn spark plugs will also activate the light. I'd suggest not panicking immediately - a yellow light means you can still drive to the repair shop, but if it turns red, shut off the engine and call a tow truck right away. Remind owners that using wrong fuel or neglecting air filter replacement for six months could cause this too - you really shouldn't skimp on those few hundred bucks when maintenance is due.
I've been driving a taxi for fifteen years and have seen the engine malfunction light come on at least a hundred times. To put it bluntly, it's the car reporting to you that there might be an issue anywhere from the fuel system to the electrical system. If the light comes on after refueling, it's likely due to poor fuel quality, with carbon deposits clogging the catalytic converter. In winter, pay special attention to faulty coolant temperature sensors falsely reporting low temperatures, causing the engine control unit to excessively enrich the fuel mixture. Just the other day, I picked up a passenger and the light came on right after starting the car. Plugging in the OBD scanner revealed a loose crankshaft position sensor connector. Honestly, there are quite a few minor issues—even something like a deteriorated fuel tank cap seal causing a vacuum leak can trigger the light. Don't fall for the repair shop's push to replace parts immediately; first clear the trouble codes and drive around to see if the issue recurs.
