Carry out On-Board Diagnostics
WARNING: This page is about a different car, the 2003 Ford RV Cutaway, 2003 Ford Econoline, 2003 Ford E550 Super Duty, 2003 Ford E450 Super Duty, and 2003 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
After a road test, with the vehicle warm and before disconnecting any connectors, carry out the Quick Test using the scan tool. Refer to the SELF-DIAGNOSTICS - CNG, FLEX-FUEL & GASOLINE or SELF-DIAGNOSTICS - 7.3L DIESEL article for diagnosis and testing of the powertrain control system.