STEP
INSPECTION
RESULTS
ACTION
1
Inspect for the following:
z
Vacuum leakage
z
Proper fuel quality (such as proper
octane, contamination,
winter/summer blend)
z
Loose bands on intake-air system
z
Cracks on intake-air system parts
z
Intake-air system restriction (such
as air cleaner element, fresh air
duct.)
Are all items normal?
Yes
Go to the next step.
No
Service if necessary.
Repeat Step 1.
2
Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON
position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?
Yes
DTC is displayed:
Go to the appropriate DTC inspection.
(See
DTC TABLE [MZI-3.7]
.)
No
No DTC is displayed:
Go to the next step.
3
Is engine overheating?
Yes
Go to symptom troubleshooting "No. 17
Cooling system concerns-Overheating".
(See
NO.17 COOLING SYSTEM
CONCERNS-OVERHEATING [MZI-
3.7]
.)
No
Go to the next step.
4
Inspect the ignition coil related wiring
harness condition (intermittent open or
short circuit) for all cylinders.
Are wiring harness conditions normal?
Yes
Go to the next step.
No
Repair the wiring harnesses.
5
Inspect the spark plug conditions.
Is spark plug wet, covered with carbon or
grayish white?
Yes
Spark plug is wet or covered with carbon:
Inspect for fuel leakage from fuel injector.
Spark plug is grayish white:
Inspect the fuel injector for clogging.
No
Install the spark plugs on original cylinders.
Go to the next step.
6
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.
7
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace the PCV valve.
Inspect the electronic throttle control system
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:10:04 AM
Page 23
© 2005 Mitchell Repair Information Company, LLC.
