Turn the ignition switch to the ON
position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
Go to appropriate DTC inspection.
(see
DTC TABLE [MZI-3.5]
.)
No
No DTC is displayed:
Go to the next step.
3
Is any other driveability concern
present?
Yes
Go to appropriate symptom
troubleshooting.
No
Go to the next step.
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?
Yes
Go to the next step.
No
Inspect for coolant leakage, cooling fan
and condenser fan operation or
thermostat operation.
5
Inspect fuel-filler cap.
(see
FUEL-FILLER CAP
INSPECTION [MZI-3.5]
.)
Is there any leakage at fuel-filler cap?
Yes
Replace the fuel-filler cap.
No
Go to the next step.
6
Inspect the front HO2S.
(see
FRONT HEATED OXYGEN
SENSOR (HO2S) INSPECTION
[MZI-3.5].
)
Is front HO2S normal?
Yes
Go to the next step.
No
Replace the front HO2S.
(see
FRONT HEATED OXYGEN
SENSOR (HO2S)
REMOVAL/INSTALLATION [MZI-
3.5].
)
7
Perform spark test.
(See
ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.5]
.)
Is strong blue spark visible at each
cylinder?
Yes
Go to the next step.
No
Repair or replace the malfunctioning
part according to spark test result.
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]
.)
Yes
Go to the next step.
No
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]
.)
9
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace the PCV valve.
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
Microsoft
Sunday, November 15, 2009 9:27:37 AM
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