DIAGNOSTIC PROCEDURE
DTC P0171, P0174 (MZI-3.7) DIAGNOSTIC PROCEDURE
CONDITION
z
The adaptive fuel strategy continuously monitors the fuel delivery hardware.
The test fails when the adaptive fuel tables reach a rich calibrated limit.
POSSIBLE CAUSE
Fuel System:
z
Damaged or leaking fuel pulse damper
z
Fuel filter plugged or dirty
z
Damaged or worn fuel pump
z
Leaking fuel pump check valve
z
Leaking/contaminated fuel injectors
z
Low fuel pressure or running out of fuel
z
Purge solenoid valve is leaking when the canister is clean
z
Fuel supply line restricted
z
Fuel rail pressure sensor bias
Exhaust System:
z
Exhaust leaks in the exhaust manifold gasket or mating gaskets before or
near the HO2S
Intake Air System:
z
Air leaks after the MAF sensor
z
Vacuum leaks
z
PCV system is leaking or the valve is stuck open
z
Improperly seated engine oil dipstick
z
Damaged or contaminated MAF sensor
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-
Yes
Perform repair or diagnosis according to
the available Service Bulletins.
z
If the vehicle is not repaired, go to
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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