Carry Out On-Board Diagnostic (OBD) Key ON Engine OFF (KOEO), Key ON Engine Running (KOER)
WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. 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 Self Test using the diagnostic tool. Refer to the INTRODUCTION - GASOLINE ENGINES article.