Mazda CX-9 Grand Touring. Manual — part 340

NO.15 EMISSION COMPLIANCE [MZI-3.7]

NO.15 EMISSION COMPLIANCE (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES

15

EMISSION COMPLIANCE

DESCRIPTION Fails emissions test.

POSSIBLE

CAUSE



Vacuum lines leakage or blockage



Cooling system malfunction



Spark plug malfunction



Leakage from intake manifold



Erratic or no signal from CMP sensor



Inadequate fuel pressure



PCV valve malfunction or incorrect valve installation



Exhaust system clogging



Fuel tank ventilation system malfunction



Fuel-filler cap malfunction



Charcoal canister damage



Air cleaner element clogging or restriction



Throttle body malfunction



Erratic signal to ignition coil



Improper air/fuel mixture ratio control operation



Bend or open circuit HO2S wiring harness



Catalyst converter malfunction



Engine internal parts malfunction



Excessive carbon is built up in combustion chamber



Improper engine compression



Improper valve timing

WARNING:

The following troubleshooting flow chart contains fuel system diagnosis and
repair procedures. Read following warnings before servicing fuel system:



Fuel vapor is hazardous. It can easily ignite, causing serious injury
and damage. Always keep sparks and flames away from fuel.



Fuel line spills and leakage are dangerous. Fuel can ignite and cause
serious injuries or death and damage. Fuel can also irritate skin and
eyes. To prevent this, always complete "BEFORE SERVICE
PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this
manual.

(See BEFORE SERVICE PRECAUTION [MZI-3.7] .)

2008 Mazda CX-9 Grand Touring

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

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Sunday, November 15, 2009 10:10:05 AM

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DIAGNOSTIC PROCEDURE

NO.15 EMISSION COMPLIANCE (MZI-3.7) DIAGNOSTIC PROCEDURE

(See AFTER SERVICE PRECAUTION [MZI-3.7] .)

CAUTION:



Disconnecting/connecting quick release connector without cleaning it
may cause damage to fuel pipe and quick release connector. Always
clean quick release connector joint area before
disconnecting/connecting, and make sure that it is free of foreign
material.

STEP

INSPECTION

RESULTS

ACTION

1

Inspect for the following:



Vacuum lines for leakage or
blockage



Electrical connections



Proper maintenance schedule
followed



Intake-air system and air
cleaner element concerns:
obstructions, leakage or
dirtiness

Are all items normal?

Yes

Go to the next step.

No

Service if necessary.

Repeat Step 1.

2

Connect the M-MDS to the DLC-2.
Turn the ignition switch to the ON
position (Engine off).
Retrieve any DTCs.
Are there any DTCs displayed?

Yes

DTC is displayed:
Go to appropriate DTC inspection.
(See DTC TABLE [MZI-3.7] .)

No

No DTC is displayed:

Go to the next step.

3

Is any other driveability concern
present?

Yes

Go to appropriate symptom troubleshooting.

No

Go to the next step.

4

Connect the M-MDS to the DLC-2.
Access ECT PID.
Warm up the engine and idle it.
Verify ECT PID is correct.
(See PCM INSPECTION [MZI-
3.7] .)
Is ECT PID correct?

Yes

Go to the next step.

No

Inspect for coolant leakage, cooling fan and

condenser fan operation or thermostat operation.

5

Inspect fuel-filler cap.
(See FUEL-FILLER CAP
INSPECTION [MZI-3.7] .)

Yes

Replace the fuel-filler cap.

2008 Mazda CX-9 Grand Touring

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:10:05 AM

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© 2005 Mitchell Repair Information Company, LLC.

Is there any leakage at fuel-filler
cap?

No

Go to the next step.

6

Inspect the front HO2S.
(See FRONT HEATED OXYGEN
SENSOR (HO2S) INSPECTION
[MZI-3.7] .)
Is front HO2S normal?

Yes

Go to the next step.

No

Replace the front HO2S.

(See FRONT HEATED OXYGEN SENSOR

(HO2S) REMOVAL/INSTALLATION [MZI-

3.7] .)

7

Perform spark test.
(See ENGINE CONTROL
SYSTEM OPERATION
INSPECTION [MZI-3.7].)
Is strong blue spark visible at each
cylinder?

Yes

Go to the next step.

No

Repair or replace the malfunctioning part

according to spark test result.

8

Install the fuel pressure gauge
between the fuel pipe and the fuel
distributor.
Start the engine and idle it.
Measure fuel line pressure during
idle.
Is fuel line pressure correct during
idle?
(See FUEL LINE PRESSURE
INSPECTION [MZI-3.7] .)

Yes

Go to the next step.

No

Low:

Inspect the fuel line for clogging.

If there is no malfunction, replace the fuel pump

unit.

(See FUEL PUMP UNIT

REMOVAL/INSTALLATION [MZI-3.7] .)

High:

Replace the fuel pump unit.

(See FUEL PUMP UNIT

REMOVAL/INSTALLATION [MZI-3.7] .)

9

Remove and shake the PCV valve.
Does the PCV valve rattle?

Yes

Go to the next step.

No

Replace the PCV valve.

10

Inspect for fuel saturation inside
charcoal canister.
Is excess amount of liquid fuel
present in canister?

Yes

Replace the charcoal canister.

No

Inspect the fuel tank vent system.

Then, go to the next step.

(See FUEL TANK INSPECTION [MZI-3.7] .)

11

visually inspect the exhaust system
part.
Is there any deformed exhaust
system part?

Yes

Replace the part.

No

Go to the next step.

12

Inspect the three-way catalytic
converter.
(See EXHAUST SYSTEM
INSPECTION [MZI-3.7] .)
Is the three-way catalytic converter
normal?

Yes

Go to the next step.

No

Replace the three-way catalytic converter.



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

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:10:05 AM

Page 68

© 2005 Mitchell Repair Information Company, LLC.

NO.16 HIGH OIL CONSUMPTION/LEAKAGE [MZI-3.7]

NO.16 HIGH OIL CONSUMPTION/LEAKAGE (MZI-3.7) DETECTION CONDITIONS AND
POSSIBLE CAUSES

DIAGNOSTIC PROCEDURE

NO.16 HIGH OIL CONSUMPTION/LEAKAGE (MZI-3.7) DIAGNOSTIC PROCEDURE

13



If malfunction remains, inspect related Service Bulletins and/or On-line Repair
Information and perform repair or diagnosis.



If vehicle is repaired, troubleshooting completed.



If vehicle is not repaired or additional diagnostic information is not available,
replace the PCM.

(See PCM REMOVAL/INSTALLATION [MZI-3.7] .)

16

HIGH OIL CONSUMPTION/LEAKAGE

DESCRIPTION

Oil consumption is excessive.

POSSIBLE CAUSE



PCV valve malfunction



Improper dipstick



Improper engine oil viscosity



Engine internal parts malfunction

STEP

INSPECTION

RESULTS

ACTION

1

Remove and shake the
PCV valve.
Does the PCV valve
rattle?

Yes

Go to the next step.

No

Replace the PCV valve.

2

Inspect for the
following:



External leakage



Proper dipstick



Proper engine oil
viscosity

Are all items normal?

Yes

Inspect the internal engine parts such as valves, valve guides,
valve stem seals, cylinder head drain passage, and piston
rings.

No

Service if necessary.

Repeat Step 2.



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

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9

Microsoft

Sunday, November 15, 2009 10:10:05 AM

Page 69

© 2005 Mitchell Repair Information Company, LLC.