HC: Fuel Delivery System HC: Introduction — 2016 workshop reference 5138

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.

• Take the recorded separation level from the previous step and subtract the amount of water added.

• Multiply the new value by 5. This new value is the percentage of ethanol in the fuel.

HC: Fuel Delivery System HC: Introduction — original illustration 1, reference 5138Original colors & callouts · Select to enlarge

Item Number	Description
1	Stopper
2	Gasoline
3	Separation Point at 14 ml
4	Ethanol and Water Mixture

• Record the calculated percentage of ethanol in the fuel.

Is any ethanol present in the fuel?

Yes	No
For E100 and flex fuel vehicles, GO to HC7 . For all others, GO to HC10 .	GO to HC11 .

Yes

For E100 and flex fuel vehicles, GO to HC7 .

For all others, GO to HC10 .

GO to HC11 .

HC7 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
GO to HC11 .	GO to HC8 .

Source reference 5138

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.