What Causes the Car to Indicate Engine Malfunction?

[ReidMarie]

Car indicating engine malfunction is caused by poor gasoline quality and excessive carbon deposits. Below are the detailed explanations: Poor Gasoline Quality: Poor gasoline quality leads to incomplete combustion of the air-fuel mixture in the cylinders, triggering the pollution warning light, and also easily causes carbon deposits. Carbon deposits in the intake tract and on the piston tops can result in poor atomization, leading to incomplete combustion and thus illuminating the pollution warning light. During cold starts, especially when the temperature drops sharply, the pollution warning light may come on due to the ECU's temperature correction issues during startup. However, once the temperature stabilizes at a certain level without fluctuations, the situation will become relatively stable. Excessive Carbon Deposits: Excessive carbon deposits can make ignition difficult, causing the ignition coil to reverse breakdown and fail, leading to poor ignition and incomplete combustion, which triggers the pollution warning light. A distinctive feature of this phenomenon is that when the ignition coil fails, the engine will continuously experience severe shaking. If the severe shaking is not continuous, the issue can essentially be ruled out as an ignition coil problem.

[VonAmelia]

Last time when I was driving, the engine warning light suddenly came on, which really startled me. This usually indicates that the onboard computer has detected some issue. There are many common causes, such as a faulty sensor like the oxygen sensor detecting abnormal emissions; problems with the ignition system such as aging spark plugs leading to poor combustion; or insufficient fuel pressure from the fuel pump causing fuel delivery interruptions. Sometimes it could be an exhaust blockage like a faulty catalytic converter, or oil pressure being too low resulting in inadequate lubrication. In my case, the check revealed it was a sensor issue, which cost a few hundred dollars to fix. If not addressed promptly, it could worsen into engine damage, costing more money and being dangerous. Before long trips, it's advisable to use an OBD scanner to first read the error codes for preliminary diagnosis.

[SanRonan]

The engine warning light gives me a headache when it comes on, but don't panic—start with some basic troubleshooting. Possible causes include a weak battery affecting the control system, clogged fuel lines or a failing pump causing unstable fuel supply, or a dirty mass airflow sensor disrupting air intake. I'll turn off the engine and restart to see if the light stays on, while also checking other dashboard warnings like high temperature. Borrowing an OBD scanner to read error codes from the port is accurate, saving both money and time. Without the tool, it's best to visit a professional shop for diagnosis—delaying could lead to a breakdown and safety risks. Regular maintenance, like replacing filters and inspecting wiring, helps prevent issues.

[DelGideon]

Never ignore the warning light as it concerns driving safety. It indicates potential serious engine issues: misfire due to ignition failure, wear caused by low oil pressure, or false sensor alerts about excessive emissions. Neglecting it may lead to engine overheating, breakdown, or even fire. I recommend pulling over immediately to check if coolant and engine oil levels are normal. A simple restart might temporarily resolve the issue if the light turns off, but persistent illumination requires professional repair. Prioritize safety and avoid risking continued driving.

[SanPatrick]

This light coming on means spending money, I know it all too well. Common causes like a bad oxygen sensor needing replacement cost a few hundred; a clogged catalytic converter can run over a thousand to fix; aging spark plugs are just a few dozen bucks cheap. I once delayed repairs and ended up with a 10,000+ engine overhaul. Others like carbon buildup in the fuel system cleaning costs hundreds, or simple circuit issues just need tightening. Car maintenance is expensive - recommend early diagnosis of error codes to decide what to fix, regular oil changes protect the engine and save big money.