Ford 2003 Mustang Workshop Manual page 2159

D1 TEST FOR FUEL TANK PRESSURE SENSOR
OPERATION
Key in OFF position.
Connect the Evaporative Emission System Leak
Tester to the fuel filler pipe.
Close the canister vent solenoid. Refer to
Vent Solenoid Closing Procedure
Pressurize the EVAP system to 3.48 kPa (14
inches H O).
2
Is the FTP (FTP V) PID reading 3.11 kPa to 3.86
kPa (12.5 to 15.5 inches H
volts)?
D2 TEST FOR BLOCKAGE IN VENTING PORTION
OF EVAP SYSTEM
Open the canister vent solenoid by selecting the
STOP button on the scan tool.
Does the pressure drop immediately?
D3 TEST FOR FUEL TANK PRESSURE SENSOR
OPERATION
Connect the Evaporative Emission System Leak
Tester to the evaporative emission test port.
Close the canister vent solenoid. Refer to
Vent Solenoid Closing Procedure
Pressurize the EVAP system to 3.48 kPa (14
inches H O).
2
Is the FTP (FTP V) PID reading 3.11 kPa to 3.86
kPa (12.5 to 15.5 inches H
volts)?
D4 TEST TO DETERMINE BLOCKAGE LOCATION
Open the canister vent solenoid.
Does the pressure drop immediately?
D5 TEST FOR PINCHED FUEL VAPOR CONTROL
VALVE TUBE
Lower the fuel tank 19.05 mm (3/4 inch).
Connect the Evaporative Emission System Leak
Tester to the fuel filler pipe.
Close the canister vent solenoid. Refer to
Vent Solenoid Closing Procedure
Pressurize the EVAP system to 3.48 kPa (14
inches H O).
2
Is the FTP (FTP V) PID reading 3.11 kPa to 3.86
kPa (12.5 to 15.5 inches H
volts)?
Test Step
in this section.
O) (4.22 to 4.90
2
in this section.
O) (4.22 to 4.90
2
in this section.
O) (4.22 to 4.90
2
Result / Action to Take
Yes
GO to D2 .
No
Canister
GO to D3 .
Yes
CARRY OUT the evaporative
emission repair verification drive
cycle. REFER to
Emission Repair Verification Drive
Cycle in this section.
No
GO to D7 .
Yes
GO to D4 .
Canister
No
REFER to the Powertrain
Control/Emissions Diagnosis (PC/ED)
manual.
Yes
GO to D5 .
No
GO to D7 .
Yes
INSTALL a new fuel vapor control
valve tube assembly. REFER to
Vapor Control Tube Assembly Valve
Canister
in this section. CARRY OUT a leak
test. REFER to
System Leak Test
the system passes the leak test,
CARRY OUT the evaporative
emission repair verification drive
cycle. REFER to
Emission Repair Verification Drive
Cycle in this section.
Evaporative
Fuel
Evaporative Emission
in this section. If
Evaporative