Mazda CX-9 Grand Touring 2007 Manual page 869

2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
11 Visually inspect for fuel leakage at fuel
injector O-ring and fuel line.
Service if necessary.
Is fuel line pressure held after ignition
switch is turned off?
(see FUEL LINE PRESSURE
INSPECTION [MZI-3.5] .)
12
NOTE:
The following test is for engine
stall with the A/C on. If other
symptom exists, go to the next
step.
Connect a pressure gauge to A/C low
and high pressure side lines.Turn the
A/C on and measure low side and high
side pressure.Are pressures within
specifications?(see REFRIGERANT
PRESSURE CHECK .)
13
NOTE:
The following test should be
performed for symptom with
cruise control ON. If other
symptoms exist, go to the next
step.
Inspect cruise control system.Is cruise
control system normal?
14 Inspect the front HO2S.
(see FRONT HEATED OXYGEN
SENSOR (HO2S) INSPECTION
[MZI-3.5]. )
Is the front HO2S normal?
15 Inspect the evaporative purge hose
between the fuel tank and the purge
valve.
Does fuel flow into evaporative purge
hose?
16 Disconnect the vacuum hose between
the purge solenoid valve and the intake
manifold from the purge solenoid
valve side.
Plug opening end of vacuum hose.
2007 Mazda CX-9 Grand Touring
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
3.5] .)
Go to the next step.
Inspect the fuel injector.
If the fuel injector is normal, replace the
fuel pump unit.
(see FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-
3.5] .)
Go to the next step.
If the A/C is always on, go to symptom
troubleshooting "No.24 A/C is always on
or A/C compressor runs continuously".
(See NO.24 A/C IS ALWAYS ON OR
A/C COMPRESSOR RUNS
CONTINUOUSLY [MZI-3.5].)
For other symptoms, inspect the
following:
Refrigerant charging amount
Condenser fan operation
Go to the next step.
Repair or replace the malfunctioning
part.
Go to the next step.
Replace the front HO2S.
(see REAR HEATED OXYGEN
SENSOR (HO2S)
REMOVAL/INSTALLATION [MZI-
3.5]. )
Inspect the check valve (two-way).
(see FUEL TANK INSPECTION
[MZI-3.5] .)
Go to the next step.
Go to the next step.
Inspect if the purge solenoid valve is
stuck open mechanically.
Inspect the evaporative emission control
system.