DIAGNOSTIC PROCEDURE
DTC P0301, P0302, P0303, P0304, P0305, P0306, P0316 (MZI-3.7) DIAGNOSTIC PROCEDURE
DTC P0305 P0305: Cylinder No.5 misfire detected
DTC P0306 P0306: Cylinder No.6 misfire detected
DTC P0316 P0316: Misfire detected on startup (first 1000 revolutions)
DETECTION
CONDITION
z
The PCM monitors the crankshaft position sensor input signal interval time. The
PCM calculates the change of the interval time for each cylinder. If the change of
interval time exceeds the pre-programmed criteria, the PCM detects a misfire in
the corresponding cylinder, when the engine is running, the PCM counts the
number of misfires that occurred at 200 crankshaft revolutions and 1,000
crankshaft revolutions and calculates the misfire ratio for each crankshaft
revolution. If the ratio exceeds the pre-programmed criteria, the PCM determines
that a misfire, which can damage the catalytic converter or affect emission
performance, has occurred.
POSSIBLE
CAUSE
z
Spark plug malfunction
z
Ignition system malfunction
z
Ignition coil malfunction
z
Fuel injector malfunction
z
Air suction in intake air system (between dynamic chamber and cylinder head)
z
Inadequate engine compression due to engine internal malfunction
z
Related connector or terminal malfunction
z
Related wiring harness malfunction
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 RELATED PENDING CODE OR
STORED DTCs
z
Turn the ignition switch off then to the ON
position (Engine off).
z
Verify related pending code or stored DTCs.
z
Are other DTCs present?
Yes
Go to the appropriate DTC
troubleshooting. (See
DTC TABLE
[MZI-3.7]
.)
No
Go to the next step.
2008 Mazda CX-9 Grand Touring
2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:08:36 AM
Page 157
© 2005 Mitchell Repair Information Company, LLC.
