DIAGNOSTIC PROCEDURE
NO.19 EXHAUST SMOKE (MZI-3.7) DIAGNOSTIC PROCEDURE
CAUTION:
z
Disconnecting/connecting quick release connector without cleaning it
may cause damage to fuel pipe and quick release connector. Always
clean quick release connector joint area before
disconnecting/connecting, and make sure that it is free of foreign
material.
STEP
INSPECTION
RESULTS
ACTION
1
What color is smoke coming from
the exhaust system?
Blue
Burning oil is indicated.
Go to the next step.
White
Water in combustion is indicated.
Go to Step 3.
Black
Rich fuel mixture is indicated.
Go to Step 4.
2
Remove and shake the PCV
valve.
Does the PCV valve rattle?
Yes
Inspect for the following:
z
Damaged valve guide, stems or valve seals
z
Blocked oil drain passage in cylinder head
z
Piston ring is not seated, seized or worn.
z
Damaged cylinder bore
If other driveability symptoms are present, return to
diagnostic index to service any additional
symptoms.
No
Replace the PCV valve.
3
Does the cooling system hold
pressure?
Yes
Inspect for the following:
z
Cylinder head gasket leakage
z
Intake manifold gasket leakage
z
Cracked or porous engine block
If other driveability symptoms are present, return to
diagnostic index to service any additional
symptoms.
No
Inspect for cause.
Inspect for the following:
z
Air cleaner restriction
Yes
Go to the next step.
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:10:05 AM
Page 75
© 2005 Mitchell Repair Information Company, LLC.
