There are a number of reasons why the check engine light may come on, from minor maintenance issues to problems with engine management systems. Today’s cars have many sensors that monitor fuel delivery, ignition timing, pollutants and airflow. If one of these fails, the vehicle’s electronic control unit will generate a diagnostic fault code and trigger the car engine warning light.

Some of the common causes are:

• A loose or faulty fuel filling cap.

• Bad oxygen or air flow sensors.

• Ignition system problems.

• Fuel system irregularities.

• Emission control system faults.

The check engine light doesn’t tell you what part failed, thus you need a proper check engine light diagnosis to find the specific cause.

What the different warning light behaviours indicate

Not all engine warning lights are created equal. How the light reacts tells us how bad the problem is.

If the car engine warning light in your car stays on, it usually means that the car has found a problem that should be checked out, although you might still be able to drive safely for short distances. However, the vehicle should be assessed as soon as possible to avoid more damage.