- Loose or damaged gas cap: A loose or damaged gas cap can cause the check engine light to come on because it allows fuel vapor to escape from the fuel tank. This can cause the engine to run lean, which can lead to a number of problems, including decreased performance, increased emissions, and engine damage.
- Oxygen sensor failure: The oxygen sensor monitors the amount of oxygen in the exhaust gas and helps the engine to regulate the fuel mixture. If the oxygen sensor fails, the engine may run rich or lean, which can cause the check engine light to come on.
- Catalytic converter failure: The catalytic converter helps to convert harmful pollutants in the exhaust gas into less harmful substances. If the catalytic converter fails, the check engine light may come on because the engine is not able to reduce emissions as effectively.
- Spark plug or ignition coil failure: Spark plugs and ignition coils are responsible for creating the spark that ignites the fuel mixture in the engine. If a spark plug or ignition coil fails, the engine may misfire, which can cause the check engine light to come on.
- Fuel injector failure: Fuel injectors are responsible for delivering fuel to the engine. If a fuel injector fails, the engine may run lean, which can cause the check engine light to come on.
If the check engine light comes on in your 1999 Dodge Durango, it is important to have it diagnosed and repaired as soon as possible. Driving with the check engine light on can damage the engine and other components of the vehicle.
