Ford 2003 Mustang Workshop Manual page 2157

Tester to the fuel filler pipe.
Pressurize the EVAP
system to 6.47 to 6.97 kPa
(26 to 28 inches H
Does the pressure drop
immediately?
B6 CHECK FOR FAILED EVAP
CANISTER PURGE VALVE OR
FUEL TANK PRESSURE
SENSOR
Use the recorded results
from the PCM DTCs.
Are DTC codes P0455 and
P1443 present?
PINPOINT TEST C: DTC P1450 EXCESSIVE VACUUM DETECTED IN
THE FUEL TANK
NOTE: Condition P1450 DTC set: more than -1.79 kPa (-7.2 inches H
C1 CHECK FOR VISUAL CAUSES OF EXCESSIVE
FUEL TANK VACUUM
Check for kinks or bends in the fuel vapor hoses
and tubes.
Visually check the EVAP canister inlet port,
canister vent solenoid filter or outlet hose for
contamination or foreign material.
Check the canister vent solenoid for blockage or
contamination.
Is a concern with a hose, tube, connection or
component visually evident?
C2 CHECK FOR BLOCKAGE BETWEEN EVAP
TEST PORT AND CANISTER VENT SOLENOID
Disconnect and plug the EVAP return tube at the
intake manifold.
Connect the Evaporative Emissions System Leak
Tester to the EVAP test port.
No
INSTALL new fuel tank vapor line(s). REPEAT pinpoint test
Step B5 to verify the repair. CARRY OUT the evaporative
O).
2
emission system leak test. REFER to
System Leak Test
leak test, CARRY OUT the evaporative emission repair
verification drive cycle. REFER to
Repair Verification Drive Cycle
Yes
INSTALL a new EVAP canister purge valve. REFER to
Evaporative Emission Canister Purge Valve
CARRY OUT the evaporative emission system leak test.
REFER to
section. If no leak is detected, CARRY OUT the evaporative
emissions repair verification drive cycle. REFER to
Evaporative Emission Repair Verification Drive Cycle
section.
No
INSTALL a new fuel tank pressure sensor. REFER to
Tank Pressure Sensor
evaporative emission system leak test. REFER to
Evaporative Emission System Leak Test
the system passes the leak test, CARRY out the
evaporative emission repair verification drive cycle. REFER
to Evaporative Emission Repair Verification Drive Cycle
this section.
Test Step
in this section. If the system passes the
in this section.
Evaporative Emission System Leak Test
in this section. CARRY OUT the
Result / Action to Take
2
Yes
REMOVE any contamination or foreign
material around fuel vapor hoses and
tubes. REPAIR the hoses, tubes or
components as necessary. After all
visual concerns are repaired, GO to
C2 .
No
GO to C2 .
Yes
GO to C3 .
No
Evaporative Emission
Evaporative Emission
in this section.
in this
in this
Fuel
in this section. If
in
O) over 30 seconds.