Why Check Engine light comes on?
The Check Engine or Service Engine Soon light or an icon resembling the engine is called, in technical terms, the Malfunction Indicator Light or MIL. The MIL light comes on when your vehicle’s computer detects a fault that can affect your vehicle’s fuel economy and the exhaust emissions. There is no button to reset the Check Engine light, but if the fault that caused it doesn’t happen again, the light will turn off by itself. If the MIL light stays on, have the problem checked out, because in some cases, the problem could get worse if not repaired in time. Think of the Check Engine light as an early warning sign. ==> not always big problem there.