DTC P0021 [MZI-3.5]
DTC P0021 (MZI-3.5) DETECTION CONDITION AND POSSIBLE CAUSES
DIAGNOSTIC PROCEDURE
DTC P0021 (MZI-3.5) DIAGNOSTIC PROCEDURE
(See
AFTER REPAIR
PROCEDURE [MZI-3.5]
.)
z
Are any DTC present?
No
Troubleshooting completed.
DTC P0021
CMP timing over-advanced (LH)
DETECTION
CONDITION
z
The PCM monitors the variable valve timing position for an over-advanced
camshaft timing. The test fails when the camshaft timing exceeds a
maximum calibrated value or remains in an advanced position.
POSSIBLE CAUSE
z
OCV (LH) malfunction
z
Spool valve in OCV (LH) is stuck in advanced position
z
Improper valve timing due to timing chain slippage
STEP
INSPECTION
ACTION
1
VERIFY FREEZE FRAME DATA HAS
BEEN RECORDED
z
Has FREEZE FRAME DATA been
recorded?
Yes
Go to the next step.
No
Record FREEZE FRAME DATA on the
repair order, then go to the next step.
2
VERIFY RELATED REPAIR
INFORMATION AVAILABILITY
z
Verify related Service Bulletins
and/or on-line repair information
availability.
z
Is any related Service Bulletins
available?
Yes
Perform repair or diagnosis according to
the available Service Bulletins.
z
If the vehicle is not repaired, go to
the next step.
No
Go to the next step.
3
VERIFY TIMING CHAIN
INSTALLATION
z
Stop the engine.
z
Remove the front cover.
z
Is the camshaft timing mark at the
correct point?
(see
TIMING CHAIN
REMOVAL/INSTALLATION
Yes
Go to the next step.
No
Reinstall the timing chain, then go to
Step 5.
2007 Mazda CX-9 Grand Touring
2007 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.5) - CX-9
Microsoft
Sunday, November 15, 2009 9:26:29 AM
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© 2005 Mitchell Repair Information Company, LLC.