Vehicle applicability: This diagnostic supplement covers multiple Ford vehicles and engines. Follow the application named in the source below. Some references apply to vehicles other than Mustang.
Is any ethanol present in the fuel?
Yes | No |
|---|---|
For flex fuel vehicles, GO to H18 . For all others, GO to H21 . | For DTCs P0171, P0174, P2195 or P2197, GO to HC2 . For all others, GO to H22 . |
H18 COMPARE THE FF_INF PID TO THE CALCULATED PERCENTAGE OF ETHANOL
Note: When determining if the FF_INF PID value is within 20% of the calculated percentage of ethanol, for example, if the calculated percentage of ethanol value is 40% then the PID value should be between 32 - 48%. The PID value cannot be less than zero.
• Ignition ON, engine OFF.
• Access the PCM and monitor the FF_INF (PER) PID.
• Compare the FF_INF PID to the calculated percentage of ethanol.
Is the FF_INF PID value within 20% of the calculated percentage of ethanol?
Yes | No |
|---|---|
For DTCs P0171, P0174, P2195 or P2197, GO to HC2 . For all others, GO to H22 . | GO to H19 . |
H19 RESET THE PERCENT ETHANOL PARAMETER IN THE PCM
Note: Certain customer fueling practices such as only fueling with small amounts of fuel or repeatedly switching between gasoline and an ethanol blend greater than E15 may prevent the PCM from learning the correct ethanol content in the fuel.
• Reset the keep alive memory (KAM). Refer to Section 2, Resetting The Keep Alive Memory (KAM).
• Ignition ON, engine running.
• Access the PCM and monitor the FF_LRND (MODE) PID.
• Drive the vehicle approximately 11.3 km (7 miles) or until the FF_LRND PID indicates yes.
Is the PID state YES?
Yes | No |
|---|---|
GO to H20 . | GO to H30 . |
H20 COMPARE THE UPDATED FF_INF PID TO THE CALCULATED PERCENTAGE OF ETHANOL
• Ignition OFF.
• Ignition ON, engine OFF.
• Access the PCM and monitor the FF_INF (PER) PID.
Is the FF_INF PID value within 20% of the calculated percentage of ethanol?
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.