z
Connect the HO2S connector.
z
Relieve the fuel pressure.
z
Connect the mechanical fuel
pressure gauge.
z
Pressurize the fuel system.
z
Turn the ignition switch to the ON
position (Engine running).
z
Allow the fuel pressure to
stabilize.
z
Turn the ignition switch off.
z
Access the PCM and control the
FP PID.
z
Run the fuel pump to obtain
maximum fuel pressure.
z
Is the fuel pressure within the
range for the vehicle being
diagnosed?
No
Go to the next step.
9
INSPECT FUEL LINE FROM FUEL
PUMP TO FUEL DELIVERY PIPE
z
Visually inspect fuel line for any
leakage.
z
Is fuel leakage found?
Yes
Replace suspected fuel line. Then go to
Step 13.
No
Inspect the low-pressure side fuel filter for
the following:
z
Foreign materials or stain inside fuel
filter. Perform the following actions
as a result.
z
If foreign material or staining is
found inside the fuel filter (low-
pressure side), clean the fuel tank
and filter.
z
If normal, replace fuel pump unit.
Then go to Step 13.
10
INSPECT FUEL INJECTOR
OPERATION
z
Remove fuel injector.
z
Inspect the injector operation.
z
Is the fuel injector normal?
Yes
Go to the next step.
No
Replace the fuel injector, then go to Step
13.
11
INSPECT FRONT HO2S OUTPUT
VOLTAGE
z
Visually inspect the HO2S circuit
Yes
Go to the next step.
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.5) - CX-9
Microsoft
Sunday, November 15, 2009 9:26:30 AM
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