Retrieve any DTCs.
Are there any DTCs displayed?
No
No DTC is displayed:
Go to the next step.
3
Access ECT PID.
Drive vehicle while monitoring PID.
(see
PCM INSPECTION [MZI-
3.5]
.)
Is PID within specification?
Yes
Go to the next step.
No
Inspect for coolant leakage, cooling fan
and condenser fan operations or
thermostat operation.
4
Perform the 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.
5
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 pump relay and fuel
pump circuit.
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]
.)
6
Inspect for variable valve timing
control system operation.
(See
ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.5]
.)
Does the variable valve timing control
system function properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning
part.
7
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace the PCV valve.
8
Visually inspect the exhaust system
part.
Is there any deformed exhaust system?
Yes
Replace the suspected part.
No
Go to the next step.
9
Inspect for contaminated MAF sensor.
Is there any contamination?
Yes
Go to the next step.
No
Inspect for cause.
10
Inspect the MAF sensor for
contamination.
Is there any contamination?
Yes
Replace MAF sensor.
No
Go to the next step.
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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