Mazda CX-9 Grand Touring 2009 Manual page 1350

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Visually inspect the CKP sensor and teeth
of crankshaft pulley.
5
Are the CKP sensor and teeth of crankshaft
pulley normal?
Inspect the spark plug condition.
6 Is spark plug wet, covered with carbon or
grayish white?
Remove and shake the PCV valve.
7
Does the PCV valve rattle?
Perform electronic throttle control system
operation inspection.
(See ENGINE CONTROL SYSTEM
8
OPERATION INSPECTION [MZI-3.7].)
Does electronic throttle control system
function properly?
visually inspect deformed exhaust system
9 part.
Is there any deformed exhaust system part?
Install the fuel pressure gauge between the
fuel pipe and the fuel distributor.
Short check connector terminal F/P to body
GND using a jumper wiring.
10 Turn the ignition switch to the ON position.
Is fuel line pressure correct with ignition
switch to ON position?
(See FUEL LINE PRESSURE
INSPECTION [MZI-3.7] .)
NOTE:
The following test is for engine
stalling with the A/C on concern. If
2008 Mazda CX-9 Grand Touring
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
VSS PID:
Inspect for intermittent open circuit of
VSS and related wiring harness.
Go to the next step.
Replace the malfunctioning part.
Spark plug is wet or covered with
carbon:
Inspect the fuel injector for fuel leakage.
Inspect spark plug and high-tension lead.
Spark plug is grayish white:
Inspect the fuel injector for clogging.
Install the spark plugs on original
cylinders.
Go to the next step.
Go to the next step.
Replace PCV valve.
Go to the next step.
Repair or replace the malfunctioning part
according to electronic throttle control
system operation inspection results.
Replace the suspected part.
Go to the next step.
Go to the next step.
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-
3.7] .)
High:
Replace the fuel pump unit.
(See FUEL PUMP UNIT
REMOVAL/INSTALLATION [MZI-
3.7] .)
Go to the next step.
If A/C is always on, go to symptom
troubleshooting "No.24 A/C is always on
or A/C compressor runs continuously".