Common Culprits

1. Spark Plugs or Wires

One of the least expensive problems and quickest fixes is a faulty spark plug. These parts are responsible for igniting the fuel mixture that allows your vehicle to run. When they are failing, you will likely notice a diminished performance. Replacing these parts quickly is necessary to maintain the integrity of other engine components, like ignition coils, oxygen sensors and the catalytic converter.

2. Oxygen Sensor

The oxygen sensor can also be the source of the illuminated dash. These sensors are essential to oxygen measurements in your system’s exhaust system. If they are not working correctly, then your car will probably burn more fuel than usual. Also, damaged sensors can result in damaged spark plugs and catalytic converter.

3. Gas Cap

One of the most common reasons for the check engine symbol lighting up is a loose gas cap or failing cap seal. Gas caps help to maintain pressure in the fuel tank, and when they are not sitting or sealed right, they can lead to reduced fuel economy and poor performance.

4. Mass Air Flow Sensor

The mass airflow sensor helps the central computer calculate how much fuel is needed to fund the engine. When this sensor is not working correctly, it can lead to more or less fuel than necessary, which can result in damage to the system, especially the catalytic converter, spark plugs and oxygen sensors.

5. Catalytic Converter

While the light on your dash can suggest that something is wrong with your catalytic converter, most likely, it will be a problem with one of the other components first. A damaged or faulty catalytic converter is usually the result of other defective or malfunctioning parts.



If your check engine light is on, then don’t ignore it. Contact Shift’n Gears and schedule an appointment to avoid further possible damage.