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):

• Erratic signal to PCM

• APP sensor or related circuit malfunction

• ECT sensor No.1 or related circuit malfunction

• IAT sensor No.1 (integrated in MAF sensor/IAT sensor No.1) or related circuit malfunction

• MAF sensor or related circuit malfunction

• MAP sensor or related circuit malfunction

• A/F sensor or related circuit malfunction

• HO2S or related circuit malfunction

• TP sensor or related circuit malfunction

• Improper fuel injection timing and amount

• Air cleaner restriction

• Intake-air system is collapsed or restricted

• Leakage at engine intake manifold and/or exhaust manifold

• Inadequate/Excessive fuel pressure

• Fuel pressure sensor malfunction

• High pressure fuel pump malfunction

• Spill valve control solenoid valve control circuit malfunction (damage to driver in PCM caused by short circuit to ground system)

• Spill valve control solenoid valve (built-into high pressure fuel pump) malfunction

• Relief valve (built-into high pressure fuel pump) malfunction

• Fuel line restricted

• Fuel pump unit malfunction

• Ignition system malfunction

• Improper engine compression

• Improper intake valve timing

• Improper exhaust valve timing

• Injector driver (built-into PCM) malfunction

WARNING:

• 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 injury 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 [SKYACTIV-G 2.5].) (See AFTER SERVICE PRECAUTION [SKYACTIV-G 2.5].)

CAUTION:

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

Item (definition)

Unit/Condition

Definition

Condition/Specification (Reference)

APP1

%

APP sensor No.1

• Accelerator pedal released: Approx. 15%

• Accelerator pedal depressed: Approx. 82%

V

• Accelerator pedal released: Approx. 0.75 V

• Accelerator pedal depressed: Approx. 4.1 V

APP2

%

APP sensor No.2

• Accelerator pedal released: Approx. 7.45%

• Accelerator pedal depressed: Approx. 41%

V

• Accelerator pedal released: Approx. 0.38 V

• Accelerator pedal depressed: Approx. 2.05 V

ECT

°C, °F

Engine coolant temperature (No.1)

• Displays ECT

V

• ECT is 20 °C {68 °F}: Approx. 3.10 V

• ECT is 40 °C {104 °F}: Approx. 2.16 V

• ECT is 60 °C {140 °F}: Approx. 1.40 V

• ECT is 80 °C {176 °F}: Approx. 0.87 V

• ECT is 100 °C {212 °F}: Approx. 0.54 V

FUEL_PRES

KPa {MPa}, mBar {Bar}, psi, in H20

Fuel pressure

• Displays fuel pressure

V

• Fuel pressure is 3.0 MPa {31 kgf/cm², 435 psi}: Approx. 0.92 V

• Fuel pressure is 4.8 MPa {49 kgf/cm², 696 psi}: Approx. 1.17 V

IAT

°C, °F

Intake air temperature (No.1)

• Displays IAT (No.1)

V

• IAT is 20 °C {68 °F}: Approx. 2.70 V

• IAT is 40 °C {104 °F}: Approx. 1.80 V

• IAT is 60 °C {140 °F}: Approx. 1.20 V

LOAD

%

Engine load

• Idle (after warm up): Approx. 17.64%

• Racing (engine speed is 2,000 rpm): Approx. 14.51%

• Racing (engine speed is 4,000 rpm): Approx. 21.17%

LONGFT1

%

Long term fuel trim

• Idle (after warm up): Approx. -2.34%

• Racing (engine speed is 2,000 rpm): Approx. -0.78%

• Racing (engine speed is 4,000 rpm): Approx. -0.78%

MAF

g/Sec

Mass air flow

• Displays MAF

V

• Switch ignition ON (engine off) (MAF: 0.59 g/s {0.078 lb/min}): Approx. 0.72 V

• Idle (after warm up) (MAF: 2.17 g/s {0.287 lb/min}): Approx. 0.86 V

• Racing (engine speed is 2,000 rpm) (MAF: 4.73 g/s {0.626 lb/min}): Approx. 1.07 V

MAP

KPa {MPa}, mBar {Bar}, psi, in H20

Manifold absolute pressure

• Displays MAP

V

• Switch ignition ON (engine off) (MAP:101 kPa {1.03 kgf/cm², 14.6 psi}): Approx. 4.07 V

• Idle (after warm up) (MAP: 33 kPa {0.34 kgf/cm², 4.8 psi}): Approx. 1.34 V

• Racing (engine speed is 2,000 rpm) (MAP: 26 kPa {0.27 kgf/cm², 3.8 psi}): Approx. 1.05 V

O2S11

µA

A/F sensor

• Idle (after warm up): Approx. -39 µA

• Deceleration fuel cut (accelerator pedal released from engine speed of 4,000 rpm or more): Approx. 3.84 mA

O2S12

V

HO2S

• Idle (after warm up): 0—1.0 V

• Deceleration fuel cut (accelerator pedal released from engine speed of 4,000 rpm or more): Approx. 0 V

RPM

RPM

Engine speed

• Displays engine speed

SHRTFT1

%

Short term fuel trim

• Idle (after warm up): Approx. 1.56%

• Racing (engine speed is 2,000 rpm): Approx. -3.12%

• Racing (engine speed is 4,000 rpm): Approx. -8.59%

TP REL

%

Throttle position signal (relative value)

• Accelerator pedal released: Approx. 12%

• Accelerator pedal depressed: Approx. 82%

VSS

KPH, MPH

Vehicle speed

• Displays vehicle speed

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 4.

Black

Rich fuel mixture is indicated.

• Go to Step 5.

2

• Inspect the PCV valve.

  (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION [SKYACTIV-G 2.5].)

• Is there any malfunction?

Yes

Replace the PCV valve.

(See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

No

Go to the next step.

3

• Inspect for the following engine internal parts:

• Damaged valve guide, stems or valve seals

• Blocked oil drain passage in cylinder head

• Piston ring is not seated, seized or worn

• Damage cylinder bore

• Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to the inspection results.

No

Engine internal parts are normal.

• If other driveability symptoms are present:

• Return to the diagnostic index to service additional symptoms.

  (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5].)

4

• Does the cooling system hold the coolant pressure?

  (See ENGINE COOLANT LEAKAGE INSPECTION [SKYACTIV-G 2.5].)

Yes

Inspect the following:

• Cylinder head gasket leakage

• Intake manifold gasket leakage

• Cracked or porous engine block

Repair or replace the malfunctioning part according to the inspection results.

• If other driveability symptoms are present:

• Return to the diagnostic index to service additional symptoms.

  (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5].)

No

Inspect for the cause.

Repair or replace the malfunctioning part according to the inspection results.

5

CAUTION:

• While performing this step, always operate the vehicle in a safe and lawful manner.

• When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.

• Access the following PIDs using the M-MDS:

  (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.5].)

• APP1

• APP2

• ECT

• IAT

• MAF

• MAP

• TP REL

• O2S11

• O2S12

• SHRTFT1

• LONGFT1

• Monitor the PIDs under the black smoke appeared engine condition.

• Do the PIDs indicate normal according to engine conditions?

  (See PCM INSPECTION [SKYACTIV-G 2.5].)

Yes

Go to the next step.

No

APP1, APP2 PIDs are not as specified:

• Inspect the APP sensor.

  (See ACCELERATOR PEDAL POSITION (APP) SENSOR INSPECTION [SKYACTIV-G 2.5].)

ECT PID is not as specified:

• Inspect the ECT sensor No.1.

  (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-G 2.5].)

IAT PID is not as specified:

• Inspect the IAT sensor No.1.

  (See INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION [SKYACTIV-G 2.5].)

MAF PID is not as specified:

• Inspect the MAF sensor.

  (See MASS AIR FLOW (MAF) SENSOR INSPECTION [SKYACTIV-G 2.5].)

MAP PID is not as specified:

• Inspect the MAP sensor.

  (See MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INSPECTION [SKYACTIV-G 2.5].)

TP REL PID is not as specified:

• Inspect the TP sensor.

  (See THROTTLE POSITION (TP) SENSOR INSPECTION [SKYACTIV-G 2.5].)

O2S11, SHRTFT1, LONGFT1 PIDs are not as specified:

• Inspect the A/F sensor.

  (See AIR FUEL RATIO (A/F) SENSOR INSPECTION [SKYACTIV-G 2.5].)

O2S12 PID is not as specified:

• Inspect the HO2S.

  (See HEATED OXYGEN SENSOR (HO2S) INSPECTION [SKYACTIV-G 2.5].)

Repair or replace the malfunctioning part according to the inspection results.

• If the malfunction remains:

• Perform the “INTERMITTENT CONCERN TROUBLESHOOTING” procedure.

  (See INTERMITTENT CONCERN TROUBLESHOOTING [SKYACTIV-G 2.5].)

6

• Perform the Fuel Injector Operation Inspection.

  (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [SKYACTIV-G 2.5].)

• Do the fuel injectors operate properly?

Yes

Go to the next step.

No

Repair or replace the malfunctioning part according to the inspection results.

7

• Inspect the following for intake-air system:

• Air cleaner restriction

• Collapsed or restricted air hose

• Leakage

• Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to the inspection results.

No

Go to the next step.

8

• Visually inspect for exhaust leakage from exhaust manifold.

• Is there any leakage?

Yes

Repair or replace the malfunctioning part according to the inspection results.

No

Go to the next step.

9

• Start the engine and warm it up completely.

• Access the FUEL_PRES PID using the M-MDS at idle.

  (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.5].)

• Is the FUEL_PRES PID value approx. 3 MPa {31 kgf/cm², 435 psi}?

Yes

Go to Step 13.

No

Lower than 3 MPa {31 kgf/cm², 435 psi}:

• Inspect the following:

• Fuel leakage at the fuel line and fuel injector

• Fuel pump

• Perform the Fuel Pump (Low-pressure Side) Operation Inspection.

  (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [SKYACTIV-G 2.5].)

• Fuel pressure sensor

  (See FUEL PRESSURE SENSOR INSPECTION [SKYACTIV-G 2.5].)

• High pressure fuel pump

  (See HIGH PRESSURE FUEL PUMP INSPECTION [SKYACTIV-G 2.5].)

• If there is any malfunction:

• Repair or replace the malfunctioning part according to the inspection results.

• If there is no malfunction:

• Go to Step 12.

Higher than 3 MPa {31 kgf/cm², 435 psi}:

• Go to the next step.

10

• Is the vehicle acceleration performance normal?

Yes

Go to the next step.

No

Go to Step 12.

11

• Inspect the fuel pressure sensor.

  (See FUEL PRESSURE SENSOR INSPECTION [SKYACTIV-G 2.5].)

• Is there any malfunction?

Yes

Replace the fuel distributor.

(See FUEL INJECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

No

Go to Step 13.

12

• Switch the ignition off.

• Disconnect the high pressure fuel pump and PCM connectors.

• Inspect for continuity between high pressure fuel pump terminal A (wiring harness-side) and body ground.

• Is there continuity?

Yes

Refer to the wiring diagram and verify whether or not there is a common connector between high pressure fuel pump terminal A and PCM terminal 1EE.

If there is a common connector:

• Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.

• Repair or replace the malfunctioning part.

If there is no common connector:

• Repair or replace the wiring harness which has a short to ground.

If the malfunction remains:

• Replace the PCM. (damage to driver in PCM)

  (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

No

Replace the high pressure fuel pump.

(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

13

• Connect the fuel pressure gauge between fuel pump and high pressure fuel pump.

• Measure the low side fuel pressure.

  (See FUEL LINE PRESSURE INSPECTION [SKYACTIV-G 2.5].)

• Is the low side fuel pressure within specification?

Specification:

• 405—485 kPa {4.13—4.94 kgf/cm², 58.8—70.3 psi}

Yes

Go to the next step.

No

Inspect the following:

• Fuel line restriction

• Fuel filter clogged

• If there is any malfunction:

• Repair or replace the malfunctioning part according to the inspection results.

• If there is no malfunction:

• Replace the fuel pump unit.

  (See FUEL PUMP UNIT REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

14

• Perform the Spark Test.

  (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [SKYACTIV-G 2.5].)

• Is a strong blue spark visible at each cylinder?

Yes

Go to the next step.

No

Repair or replace the malfunctioning part according to the inspection results.

15

• Measure the compression pressure for each cylinder.

  (See COMPRESSION INSPECTION [SKYACTIV-G 2.5].)

• Are compression pressures within specification?

Specification:

• Compression

• Standard: 954 kPa {9.73 kgf/cm², 138 psi} (300 rpm)

• Minimum: 763 kPa {7.78 kgf/cm², 111 psi} (300 rpm)

• Maximum difference between cylinders: 161 kPa {1.64 kgf/cm², 23.4 psi} (300 rpm)

NOTE:

• Because the SKYACTIV-G 2.5 retards the intake valve closing timing, compression pressure is low.

Yes

Injector driver malfunction.

• Replace the PCM.

  (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.5].)

If the problem remains, overhaul the engine.

No

Inspect the following:

• Damaged valve seat

• Worn valve stem and valve guide

• Worn or stuck piston ring

• Worn piston, piston ring or cylinder

• Improper intake valve timing

• Improper exhaust valve timing

Service if necessary.

16

Verify the test results.

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

  (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5].)

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

• If the vehicle is repaired, troubleshooting is completed.

• If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.