Mazda CX-9 Grand Touring 2009 Manual page 1359

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Is there any leakage at fuel-filler
cap?
Inspect the front HO2S.
(See FRONT HEATED OXYGEN
6 SENSOR (HO2S) INSPECTION
[MZI-3.7] .)
Is front HO2S normal?
Perform spark test.
(See ENGINE CONTROL
SYSTEM OPERATION
7
INSPECTION [MZI-3.7].)
Is strong blue spark visible at each
cylinder?
Install the fuel pressure gauge
between the fuel pipe and the fuel
distributor.
Start the engine and idle it.
Measure fuel line pressure during
8
idle.
Is fuel line pressure correct during
idle?
(See FUEL LINE PRESSURE
INSPECTION [MZI-3.7] .)
Remove and shake the PCV valve.
9
Does the PCV valve rattle?
Inspect for fuel saturation inside
charcoal canister.
10
Is excess amount of liquid fuel
present in canister?
visually inspect the exhaust system
part.
11
Is there any deformed exhaust
system part?
Inspect the three-way catalytic
converter.
(See EXHAUST SYSTEM
12
INSPECTION [MZI-3.7] .)
Is the three-way catalytic converter
normal?
Verify test results.
If normal, return to diagnostic index to service any additional symptoms.
(See SYMPTOM DIAGNOSTIC INDEX [MZI-3.7].)
2008 Mazda CX-9 Grand Touring
No
Yes Go to the next step.
(See FRONT HEATED OXYGEN SENSOR
No
(HO2S) REMOVAL/INSTALLATION [MZI-
Yes Go to the next step.
Repair or replace the malfunctioning part
No
Yes Go to the next step.
If there is no malfunction, replace the fuel pump
No
REMOVAL/INSTALLATION [MZI-3.7] .)
REMOVAL/INSTALLATION [MZI-3.7] .)
Yes Go to the next step.
No
Yes Replace the charcoal canister.
No
(See FUEL TANK INSPECTION [MZI-3.7] .)
Yes Replace the part.
No
Yes Go to the next step.
No Replace the three-way catalytic converter.
Go to the next step.
Replace the front HO2S.
3.7] .)
according to spark test result.
Low:
Inspect the fuel line for clogging.
unit.
(See FUEL PUMP UNIT
High:
Replace the fuel pump unit.
(See FUEL PUMP UNIT
Replace the PCV valve.
Inspect the fuel tank vent system.
Then, go to the next step.
Go to the next step.