Mazda CX-9 Grand Touring. Manual — part 342

NO.19 EXHAUST SMOKE [MZI-3.7]

NO.19 EXHAUST SMOKE (MZI-3.7) DETECTION CONDITIONS AND POSSIBLE CAUSES

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

19

EXHAUST SMOKE

DESCRIPTION Blue, black, or white smoke from exhaust system

POSSIBLE

CAUSE

Blue smoke (Burning oil):



PCV valve malfunction



Engine internal oil leakage

White smoke (Water in combustion):



Cooling system malfunction (coolant loss)



Engine internal coolant leakage

Black smoke (Rich fuel mixture):



Air cleaner restriction



Intake-air system is collapsed or restricted.



Fuel return line is restricted.



Excessive fuel pressure



Improper engine compression



Injector fuel leakage



Ignition system malfunction

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] .)

(See AFTER SERVICE PRECAUTION [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 74

© 2005 Mitchell Repair Information Company, LLC.

DIAGNOSTIC PROCEDURE

NO.19 EXHAUST SMOKE (MZI-3.7) DIAGNOSTIC PROCEDURE

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

What color is smoke coming from
the exhaust system?

Blue

Burning oil is indicated.
Go to the next step.

White

Water in combustion is indicated.

Go to Step 3.

Black

Rich fuel mixture is indicated.
Go to Step 4.

2

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

Yes

Inspect for the following:



Damaged valve guide, stems or valve seals



Blocked oil drain passage in cylinder head



Piston ring is not seated, seized or worn.



Damaged cylinder bore

If other driveability symptoms are present, return to
diagnostic index to service any additional
symptoms.

No

Replace the PCV valve.

3

Does the cooling system hold
pressure?

Yes

Inspect for the following:



Cylinder head gasket leakage



Intake manifold gasket leakage



Cracked or porous engine block

If other driveability symptoms are present, return to
diagnostic index to service any additional
symptoms.

No

Inspect for cause.

Inspect for the following:



Air cleaner restriction

Yes

Go to the next step.

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 75

© 2005 Mitchell Repair Information Company, LLC.

NO.20 FUEL ODOR (IN ENGINE COMPARTMENT) [MZI-3.7]

4



Collapsed or restricted
intake-air system



Restricted fuel return line

Are all items normal?

No

Service if necessary.

Repeat Step 4.

5

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 the appropriate DTC inspection.
(See DTC TABLE [MZI-3.7] .)

No

No DTC is displayed:

Go to the next step.

6

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] .)

7

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

Yes

Inspect the CMP sensor.
(See CAMSHAFT POSITION (CMP) SENSOR
INSPECTION [MZI-3.7] .)

No

Repair or replace the malfunctioning part according

to spark test result.

8



Verify test results.



If normal, return to diagnostic index to service any additional symptoms.

(See SYMPTOM DIAGNOSTIC INDEX [MZI-3.7].)



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] .)

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 76

© 2005 Mitchell Repair Information Company, LLC.

NO.20 FUEL ODOR (IN ENGINE COMPARTMENT) (MZI-3.7) DETECTION CONDITIONS AND
POSSIBLE CAUSES

DIAGNOSTIC PROCEDURE

NO.20 FUEL ODOR (IN ENGINE COMPARTMENT) (MZI-3.7) DIAGNOSTIC PROCEDURE

20

FUEL ODOR (IN ENGINE COMPARTMENT)

DESCRIPTION Gasoline fuel smell or visible leakage

POSSIBLE

CAUSE



Excessive fuel pressure



Purge solenoid valve malfunction



Fuel tank vent system blockage



Charcoal canister malfunction



Fuel leakage from fuel system

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] .)

(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

Visually inspect for fuel leakage at fuel
injector O-ring and fuel line.
Service if necessary.
Install the fuel pressure gauge between the
fuel pipe and the fuel distributor.
Start engine and idle it.
Measure fuel line pressure during idle.
Is fuel line pressure correct during idle?

Yes

Go to the next step.

No

Replace the fuel pump unit.

(See FUEL PUMP UNIT

REMOVAL/INSTALLATION [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 77

© 2005 Mitchell Repair Information Company, LLC.