Some 2018-2020 F-150 vehicles equipped with a 5.0L engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTCs) P0172, P0173, P0174 and/or P0175. This may be due to incorrect flex fuel learning, which is often caused by customer refueling habits or a stuck open evaporative emissions purge valve. Refer to pinpoint test H in the Powertrain Control/Emissions Diagnosis (PC/ED) Manual for diagnostics and Flex Fuel GSB for additional flex fuel system information and diagnostic tips.
