2014 Flex Workshop Manual

SECTION 310-00: Fuel System — General Information	2014 Flex Workshop Manual
DIAGNOSIS AND TESTING	Procedure revision date: 06/28/2013

Fuel System

Symptom Chart: Fuel System

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to Section 100-00, Diagnostic Methods for information regarding Ford-specific diagnostic practices.

NOTE: Refer to the Description and Operation, Intelligent Access with Push Button Start. REFER to Section 419-01C to review the procedures for achieving the various ignition states (ignition OFF, ignition in ACCESSORY, ignition ON and ignition START) on vehicles with this feature.

Symptom Chart: Fuel System

Condition	Possible Sources	Actions
Slow to fill	Fuel tank filler pipe Fuel tank filler pipe vent tube, if equipped EVAP system Fuel tank inlet check valve (part of the fuel tank) Fuel level vent valve (part of the fuel tank) Fuel system fresh air inlet	REFER to Section 310-00, GO to Pinpoint Test A .
All other fuel system concerns	Fuel system components	REFER to the PC/ED manual.

Pinpoint Tests

Slow to Fill

Diagnostic Overview

Slow to Fill

Normal Operation and Fault Conditions

Under normal operation, fuel should flow at a steady rate through the fuel tank filler pipe into the fuel tank. As fuel enters the fuel tank air is vented through the filler pipe or the ORVR system.

Fuel tank filler pipe vent tube, if equipped
Fuel tank filler pipe
EVAP system
Fuel tank inlet check valve (part of the fuel tank)
Fuel level vent valve, if equipped (part of the fuel tank)
Fuel system fresh air inlet

PINPOINT TEST A: Slow to Fill

Test Step	Result / Action to Take
A1 CARRY OUT INSPECTION AND VERIFICATION
Carry out inspection and verification. Was the cause of the concern found?	Yes REPAIR or INSTALL new components to correct the concern. No GO to A2 .
A2 CHECK THE SYSTEM FOR ANY EVAP DTCs
Connect the scan tool. Check the system for any of the following EVAP DTCs : P0446, P0451, P0452, P0453, P0454, P1450, P1451 and P260F. Are any of these DTCs present?	Yes REFER to PC/ED manual, section 3 Symptom Charts. No GO to A3 .
A3 MONITOR THE FTP WHILE FILLING THE FUEL TANK
Monitor the FTP reference value while filling the fuel tank. Refer to the appropriate vehicle/engine table in PC/ED manual, section 6 Reference Values. Is FTP within specification?	Yes GO to A5 . No GO to A4 .
A4 MONITOR THE FTP WHILE FILLING THE FUEL TANK WITH THE EVAP SYSTEM DISCONNECTED
Disconnect the fuel tank-to-Evaporative Emission (EVAP) canister quick connect coupling at the EVAP canister. Monitor the FTP reference value while filling the fuel tank. Refer to the appropriate vehicle/engine table in PC/ED manual. Is FTP within specification?	Yes INSPECT the EVAP system for blockage or restrictions. REPAIR the blockage or restriction. If the blockage or restriction cannot be repaired, INSTALL new EVAP system components. No GO to A5 .
A5 CHECK THE FUEL TANK FILLER PIPE ASSEMBLY FOR BLOCKAGE OR RESTRICTION
Remove the fuel tank filler pipe assembly. REFER to Section 310-01, Fuel Tank Filler Pipe . Inspect the fuel tank filler pipe and fuel tank filler pipe vent tube (if equipped) for a blockage or restriction. Is the fuel tank filler pipe or fuel tank filler pipe vent tube (if equipped) blocked or restricted?	Yes If possible, REPAIR the blockage or restriction. If the blockage or restriction cannot be repaired, INSTALL a new fuel tank filler pipe or fuel tank filler pipe vent tube. No GO to A6 .
A6 CHECK THE FRESH AIR LINE FOR BLOCKAGE OR RESTRICTION
Separate the fresh air hose vent cap from cross member. Remove the fresh air hose vent cap from the tube. Inspect the tube and cap for blockages (mud, spider nests, etc.). Is the fresh air hose vent cap or hose blocked or restricted?	Yes Disconnect and blow-out rubber fuel vapor tube that connects to the rear-most port of the canister with compressed air. Replace the fresh air hose vent cap. No GO to A7 .
A7 CHECK THE FUEL TANK EVAP LINE FOR BLOCKAGE OR RESTRICTION
Disconnect the large 0.7 cm (5/8 in) EVAP line connector at the upper front canister where It connects from the fuel tank to the carbon canister assembly Inlet. Quick Connect Coupling Is there presence of liquid fuel in the line?	Yes Replace the EVAP canister, the EVAP canister purge valve, the fuel vapor tube assembly Section 303-13 and the fuel tank Section 310-01 . No GO to A8 .
A8 CHECK THE FUEL TANK INLET CHECK VALVE
Inspect the fuel tank inlet check valve for restriction or sticking. Is the fuel tank inlet check valve restricted or sticking?	Yes If possible, REPAIR the restriction. If the restriction cannot be repaired, INSTALL a new fuel tank. REFER to Section 310-01, Fuel Tank . No INSTALL a new fuel tank. REFER to Section 310-01, Fuel Tank .