Mazda CX-9 Grand Touring 2007 Manual page 882

2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
Turn the ignition switch to the ON
position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
3 Is any other driveability concern
present?
4 Connect the M-MDS to the DLC-2.
Access ECT PID.
Warm up the engine and idle it.
Verify ECT PID is correct.
(see PCM INSPECTION [MZI-
3.5] .)
Is ECT PID correct?
5 Inspect fuel-filler cap.
(see FUEL-FILLER CAP
INSPECTION [MZI-3.5] .)
Is there any leakage at fuel-filler cap?
6 Inspect the front HO2S.
(see FRONT HEATED OXYGEN
SENSOR (HO2S) INSPECTION
[MZI-3.5]. )
Is front HO2S normal?
7 Perform spark test.
(See ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.5].)
Is strong blue spark visible at each
cylinder?
8 Install the fuel pressure gauge between
the fuel pipe and the fuel distributor.
Start the engine and idle it.
Measure fuel line pressure during idle.
Is fuel line pressure correct during
idle?
(see FUEL LINE PRESSURE
INSPECTION [MZI-3.5] .)
9 Remove and shake the PCV valve.
Does the PCV valve rattle?
2007 Mazda CX-9 Grand Touring
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Go to appropriate DTC inspection.
(see DTC TABLE [MZI-3.5] .)
No DTC is displayed:
Go to the next step.
Go to appropriate symptom
troubleshooting.
Go to the next step.
Go to the next step.
Inspect for coolant leakage, cooling fan
and condenser fan operation or
thermostat operation.
Replace the fuel-filler cap.
Go to the next step.
Go to the next step.
Replace the front HO2S.
(see FRONT HEATED OXYGEN
SENSOR (HO2S)
REMOVAL/INSTALLATION [MZI-
3.5]. )
Go to the next step.
Repair or replace the malfunctioning
part according to spark test result.
Go to the next step.
Low:
Inspect the fuel line for clogging.
If there is no malfunction, replace the
fuel pump unit.
(see FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-
3.5] .)
High:
Replace the fuel pump unit.
(see FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-
3.5] .)
Go to the next step.
Replace the PCV valve.