DIAGNOSTIC PROCEDURE
EXHAUST SMOKE DIAGNOSTIC PROCEDURE TABLE
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:
Damaged valve guide, stems or
valve seals
Blocked oil drain passage in
cylinder head
Piston ring is not seated, seized
or worn.
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:
Cylinder head gasket leakage
Intake manifold gasket leakage
Cracked or porous engine block
If other driveability symptoms are
present, return to diagnostic index to
service any additional symptoms.
No
Inspect for cause.
4
Inspect for the
following:
Air cleaner
restriction
Yes
Go to the next step.
2007 Mazda MX-5 Miata Sport
2007 ENGINE PERFORMANCE Symptom Troubleshooting - MX-5 Miata
Microsoft
Thursday, July 09, 2009 2:42:10 PM
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