crankshaft pulley normal?
No
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
Attempt to start engine at part throttle.
Does engine run smoothly at part
throttle?
Yes
Inspect the electronic throttle control
system operation.
(See
ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.5]
.)
No
Go to the next step.
9
Install the fuel pressure gauge between
the fuel pipe and fuel distributor.
Short check connector terminal F/P to
body GND using a jumper wiring.
Turn the ignition switch to the ON
position.
Is fuel line pressure correct with
ignition switch ON?
(see
FUEL LINE PRESSURE
INSPECTION [MZI-3.5]
.)
Yes
Go to the next step.
No
Zero or low:
Inspect the fuel pump relay and the 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]
.)
10
Is the fuel line pressure held after
ignition switch is turned off?
(see
FUEL LINE PRESSURE
INSPECTION [MZI-3.5]
.)
Yes
Go to the next step.
No
Inspect the fuel injector.
(see
FUEL INJECTOR INSPECTION
[MZI-3.5]
.)
If the fuel injector is normal, replace the
fuel pump unit.
(see
FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-
3.5]
.)
11
Disconnect a vacuum hose from purge
solenoid valve and plug opening end of
vacuum hose.
Start engine.
Is starting condition improved?
Yes
Inspect if the purge solenoid valve is
stuck open.
No
Go to the next step.
12
Inspect the MAF sensor for following:
z
Contamination
z
MAF sensor terminal B voltage
(GND circuit)
Yes
Repair or replace the malfunctioning
part.
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 9:27:36 AM
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