The “Check Engine”, “Service Engine Soon” light or MIL (Malfunction Indicator Lamp) means that the vehicle computer detects a system not functioning within its pre-programmed parameters. Many things can trigger the check engine light: A loose fuel cap (computer sees a pressure loss in the fuel system), a vacuum leak, a bad fuel pump, a bad spark plug, a plugged fuel filter, a broken, pinched or disconnected wire, a lazy oxygen sensor, or a malfunctioning coolant temperature sensor.
Don’t worry! What were the driving conditions and circumstances when the light first came on? Did it come on shortly after you filled the fuel tank? Did it come on after an extended drive in the summer heat? These clues can help the technician find the problem quicker saving you some money.
If the MIL is flashing, you need to get to your repair facility ASAP! This indicates that your vehicle’s emission control system could soon be damaged.
When the check engine light comes on, make an appointment to have your vehicle tested. A technician will scan the computer for codes that help him find the malfunctioning system and begin the repair process.