Mazda CX-9 Grand Touring. Manual — part 272

DTC P0454 [MZI-3.7]

DTC P0454 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES

DIAGNOSTIC PROCEDURE

DTC P0454 (MZI-3.7) DIAGNOSTIC PROCEDURE

memory using the M-MDS.



Start the engine and warm it up
completely.



Is same DTC present?

No

Go to the next step.

10

VERIFY AFTER REPAIR
PROCEDURE



Perform the "After Repair
Procedure". (See AFTER REPAIR
PROCEDURE [MZI-3.7].)



Are any DTCs present?

Yes

Go to the applicable DTC inspection. (See DTC
TABLE [MZI-3.7].)

No

Troubleshooting completed.

DTC P0454

Fuel tank pressure sensor intermittent

DETECTION

CONDITION



The fuel tank pressure changes more than 14 inches of water in 0.10 s.

POSSIBLE CAUSE



Intermittent open or short in the fuel tank pressure sensor or the fuel
tank pressure sensor signal



Fuel tank pressure sensor malfunction

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS
BEEN RECORDED



Has FREEZE FRAME DATA been
recorded?

Yes Go to the next step.

No

Record FREEZE FRAME DATA on the repair

order, then go to the next step.

2

VERIFY RELATED REPAIR
INFORMATION AVAILABILITY



Verify related Service Bulletins and/or
on-line repair information availability.



Is any related Service Bulletins
available?

Yes

Perform repair or diagnosis according to the
available Service Bulletins.



If the vehicle is not repaired, go to the
next step.

No

Go to the next step.

3

VERIFY RELATED PENDING CODE
OR STORED DTCs



Turn the ignition switch off then to the
ON position (Engine off).

Yes

Go to the appropriate DTC troubleshooting. (See
DTC TABLE [MZI-3.7].)

Perform the "INTERMITTENT CONCERN

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

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DTC P0455 [MZI-3.7]

DTC P0455 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES



Verify related pending code or stored
DTCs.



Is other DTCs present?

No

TROUBLESHOOTING". Then go to the next

step.

4

VERIFY TROUBLESHOOTING OF
DTC P0454 HAS BEEN COMPLETED



Verify that all disconnected
connectors reconnected.



Clear the DTC from the PCM memory
using the M-MDS.



Perform the "KOEO or KOER self-
test" using the M-MDS.

(See KOEO/KOER SELF TEST
[MZI-3.7].)



Is the PENDING CODE for the DTC
present?

Yes

Replace the PCM, then go to the next step. (See
PCM REMOVAL/INSTALLATION [MZI-
3.7] .)

No

Go to the next step.

5

VERIFY AFTER REPAIR
PROCEDURE



Perform the "AFTER REPAIR
PROCEDURE". (See AFTER
REPAIR PROCEDURE [MZI-3.7].)



Are any DTCs present?

Yes

Go to the applicable DTC inspection. (See DTC
TABLE [MZI-3.7].)

No

Troubleshooting completed.

DTC P0455

Evaporative emission system leak detected (gross leak/no flow)

DETECTION

CONDITION



P0455 indicates that a substantial leak or blockage has been detected in the
EVAP system when there is - 1.74 kPa (PID FTP_H2O displays "-7.0") or less
vacuum for a 30 seconds evaluation time.

POSSIBLE

CAUSE



After-market EVAP hardware (such as fuel-filler cap) not conforming to
required specifications.



Disconnected or cracked fuel chopping timer tube, CV solenoid valve outlet
tube or EVAP return tube.



CV solenoid valve stuck closed



Damaged or missing fuel-filler cap.



Insufficient fuel-filler cap installation.



Loose fuel vapor hose/tube connections to EVAP system components.



Blockages or restrictions in fuel vapor hoses/tubes.

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:38 AM

Page 222

© 2005 Mitchell Repair Information Company, LLC.

DIAGNOSTIC PROCEDURE

DTC P0455 (MZI-3.7) DIAGNOSTIC PROCEDURE



Rollover valve blocked or fuel shut-off valve.



CV solenoid valve stuck open.



Mechanically inoperative Fuel tank pressure sensor.



Damaged charcoal canister.

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA
HAS BEEN RECORDED



Has FREEZE FRAME DATA
been recorded?

Yes Go to the next step.

No

Record FREEZE FRAME DATA on the repair order,

then go to the next step.

2

VERIFY RELATED REPAIR
INFORMATION AVAILABILITY



Verify related Service Bulletins
and/or on-line repair information
availability.



Is any related Service Bulletins
available?

Yes

Perform repair or diagnosis according to the
available Service Bulletins.



If the vehicle is not repaired, go to the next
step.

No

Go to the next step.

3

VERIFY RELATED PENDING
CODE OR STORED DTCs



Turn the ignition switch off then
to the ON position (Engine off).



Verify related pending code or
stored DTCs.



Are other DTCs present?

Yes

Go to the appropriate DTC troubleshooting. (See
DTC TABLE [MZI-3.7].)

No

Go to the next step.

4

VISUALLY INSPECT FOR LARGE
EVAP SYSTEM LEAK



Check for the presence of a fuel-
filler cap. Do not tighten or check
for correct installation at this
time.



Verify that both the input port
vacuum hose and EVAP return
tube are attached to the CV
solenoid valve.



Verify that the CV solenoid valve
is properly attached to the
charcoal canister.

Yes

Repair or replace the EVAP components if
necessary. (See FUEL TANK INSPECTION
[MZI-3.7] .)
(See FUEL TANK PRESSURE SENSOR
INSPECTION [MZI-3.7] .)
(See CHARCOAL CANISTER, CANISTER
VENT (CV) SOLENOID VALVE, AIR FILTER

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:38 AM

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© 2005 Mitchell Repair Information Company, LLC.



Visually inspect for disconnected
or cracked fuel vapor hoses/tubes
between the intake manifold and
the following components:



CV solenoid valve



Charcoal canister



Fuel shut-off valve



Check for damage to the fuel-
filler pipe and the fuel tank.



Is a concern visually evident?

COMPONENT REMOVAL/INSTALLATION
[MZI-3.7] .)
Go to Step 7.

No

Go to the next step.

5

INSPECT FOR EVAP SYSTEM
LEAKS



Disconnect the EVAP return tube
from the intake manifold and plug
the EVAP return tube.



Connect the EVAP System Leak
Tester to the EVAP test port.



Perform the EVAP System Leak
Test. (See ENGINE CONTROL
SYSTEM OPERATION
INSPECTION [MZI-3.7] .)



Does the pressure stay above 1.99
kPa (PID FTP_H2O displays
"8")?

Yes Go to the next step.

No

Verify that the fuel-filler cap is installed correctly.

Repair or install a new components if necessary. Go

to Step 8.

6

INSPECT FOR BLOCKAGE
BETWEEN CV SOLENOID VALVE
AND FUEL VAPOR HOSE JOINT



Turn the ignition switch to the
ON position (Engine off)



Using M-MDS tester, select the
Diagnostic Data Link.



Select the PCM.



Select the Active Command
Modes.



Select the Output Test Mode.



Close the CV solenoid valve
using the EVMV PID.



Pressurize the EVAP system to
3.48 kPa (PID FTP_H2O displays
"14").

Yes Go to the next step.

No

Replace the fuel tank vapor line(s). Go to Step 8.

2008 Mazda CX-9 Grand Touring

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:08:38 AM

Page 224

© 2005 Mitchell Repair Information Company, LLC.