4
Inspect compression pressure at
suspected malfunctioning cylinder.
Is compression pressure correct?
(see
COMPRESSION INSPECTION
[MZI-3.5]
.)
Yes
Go to the next step.
No
Repair or replace the malfunctioning
part.
5
Install all spark plugs.
Perform the spark test at suspected
malfunctioning cylinder.
Is strong blue spark visible?
(Compare with normal cylinder.)
Yes
Go to the next step.
No
Repair or replace the malfunctioning
part.
6
Install the fuel pressure gauge between
fuel filter and fuel distributor.
Short check connector terminal F/P to
body GND using a jumper wiring.
Turn the ignition switch to the ON
position (Engine off).
Is the fuel line pressure correct with the
ignition switch at ON?
(see
FUEL LINE PRESSURE
INSPECTION [MZI-3.5]
.)
Yes
Inspect fuel injector for the following:
z
Open or short circuit in injector
z
Leakage
z
Injection volume
No
Zero or 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]
.)
7
Inspect the spark plug for the
following.
z
Heat range
z
Air gap
Is the spark plug normal?
Yes
Go to the next step.
No
Replace the spark plug.
(see
SPARK PLUG
REMOVAL/INSTALLATION [MZI-
3.5]
.)
8
Remove the suspected fuel injector.
Inspect the following:
z
Resistance
z
Fuel injection volume
(see
FUEL INJECTOR
INSPECTION [MZI-3.5]
.)
Yes
Inspect for open circuit in wiring
harness between fuel injector connector
terminal A and PCM at the following
terminals:
z
For No.1 cylinder: 2BJ
z
For No.2 cylinder: 2BM
z
For No.3 cylinder: 2BF
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE Symptom Troubleshooting (MZI-3.5) - CX-9
Microsoft
Sunday, November 15, 2009 9:27:38 AM
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