MAF sensor and related wiring harness.
TP1, TP2 PID:
Inspect if output signal TP sensor
changes smoothly.
IAT PID:
Inspect for air suction in intake-air
system.
If normal, inspect intermittent short
circuit of IAT sensor and related wiring
harnesses.
VSS PID:
Inspect for intermittent open circuit of
VSS and related wiring harness.
5
Visually inspect the CKP sensor and
teeth of crankshaft pulley.
Are the CKP sensor and teeth of
crankshaft pulley normal?
Yes
Go to the next step.
No
Replace the malfunctioning part.
6
Inspect the spark plug condition.
Is spark plug wet, covered with carbon
or grayish white?
Yes
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.
No
Install the spark plugs on original
cylinders.
Go to the next step.
7
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace PCV valve.
8
Perform electronic throttle control
system operation inspection.
(See
ENGINE CONTROL SYSTEM
OPERATION INSPECTION [MZI-
3.5]
.)
Does electronic throttle control system
function properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning
part according to electronic throttle
control system operation inspection
results.
9
visually inspect deformed exhaust
system part.
Is there any deformed exhaust system
part?
Yes
Replace the suspected part.
No
Go to the next step.
10
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.
Turn the ignition switch to the ON
position.
Is fuel line pressure correct with
Yes
Go to the next step.
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.
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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