* Oxygen sensor failure
* Spark plug failure
* Catalytic converter failure
* Evaporative emissions system leak
* Mass air flow sensor failure
* Throttle position sensor failure
* Transmission control module failure
If the check engine light is on, it is important to have the vehicle diagnosed by a qualified technician to determine the cause of the problem. Continuing to drive the vehicle with the check engine light on can damage the vehicle's engine and transmission.
Here are some additional tips for troubleshooting a check engine light in a 2002 Ford Expedition:
* Check the gas cap to make sure it is tight. A loose gas cap can cause the check engine light to come on.
* Have the vehicle's emissions system inspected. A faulty emissions system can cause the check engine light to come on.
* Have the vehicle's spark plugs and oxygen sensors checked. Worn spark plugs or oxygen sensors can cause the check engine light to come on.
* Have the vehicle's catalytic converter checked. A damaged catalytic converter can cause the check engine light to come on.
If you are experiencing any other problems with your 2002 Ford Expedition, such as engine stalling, transmission problems, or strange noises, it is important to have the vehicle diagnosed by a qualified technician as soon as possible.
