DTC P0172, P0175 [MZI-3.7]
DTC P0172, P0175 (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES
temperature.
z
Access the PCM and monitor the HO2S
signal PID.
z
Wiggle, shake, and bend small sections of the
wiring harness while working from the
sensor to the PCM.
z
While monitoring the HO2S PID, does the
HO2S stop switching?
No
Go to the next step.
13
VERIFY TROUBLESHOOTING OF DTC
P0171, P0174 HAS BEEN COMPLETED
z
Verify that all disconnected connectors are
reconnected.
z
Turn the ignition switch to the ON position
(Engine off).
z
Clear the DTC from the PCM memory using
the M-MDS.
z
Start the engine and run it at idle.
z
Retrieve DTCs using the M-MDS.
z
Is the PENDING CODE for this DTC
present?
Yes
Replace PCM, then go to the next step.
(See
PCM
REMOVAL/INSTALLATION [MZI-
3.7]
.)
No
Go to the next step.
14
VERIFY AFTER REPAIR PROCEDURE
z
Perform "AFTER REPAIR PROCEDURE".
(See
AFTER REPAIR PROCEDURE
[MZI-3.7]
.)
z
Are any DTC present?
Yes
Go to the applicable DTC inspection.
(See
DTC TABLE [MZI-3.7]
.)
No
Troubleshooting completed.
DTC P0172
P0172: System too rich (RH)
DTC P0175
P0175: System too rich (LH)
DETECTION
CONDITION
z
P0172 indicates that the fuel/air ratio is too rich (RH).
z
P0175 indicates that the fuel/air ratio is too rich (LH).
z
The adaptive fuel strategy continuously monitors the fuel delivery hardware.
The test fails when the adaptive fuel tables reach a rich calibrated limit.
Fuel System:
z
Damaged or leaking fuel pulse damper
z
Leaking fuel injectors
z
Fuel return line restricted
2008 Mazda CX-9 Grand Touring
2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9
Microsoft
Sunday, November 15, 2009 10:08:35 AM
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© 2005 Mitchell Repair Information Company, LLC.
