15

EMISSION COMPLIANCE

DESCRIPTION

• Fails emissions test.

POSSIBLE CAUSE

• Engine overheating

• Cooling system malfunction

• PCM DTC is stored

• Incorrect fuel injection timing

• Incorrect ignition timing

• Spark plug malfunction

• Ignition coil malfunction

• Purge solenoid valve malfunction

• Inadequate fuel pressure

• Fuel leakage at the fuel line and/or fuel injector

• Fuel pressure sensor or related circuit 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 restriction

• Fuel pump unit malfunction

• Air leakage from intake-air system

• Vacuum lines leakage or blockage

• Charcoal canister damage

• Improper engine coolant level

• Excessive carbon built-up in combustion chamber

• Improper engine compression

• Improper intake valve timing

• Improper exhaust valve timing

• Exhaust system and/or TWC restriction

• Exhaust gas leakage from the exhaust system

• TWC malfunction (PCM DTC is stored.)

• Positive crankcase ventilation system malfunction

• PCV valve malfunction or incorrect valve installation

• Clogging in positive crankcase ventilation system hoses (PCV valve hose, ventilation hose)

WARNING:

• The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:

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

• Highly pressurized fuel may spray out if the fuel line is cut. Due to the following dangers occurring with a fuel spray, always complete the “Fuel Line Safety Procedure” to prevent the fuel from spraying. (See BEFORE SERVICE PRECAUTION [SKYACTIV-G 2.0].)

• Fuel may cause irritation if it comes in contact with skin and eyes.

• If fuel ignites and causes a fire, it may lead to serious injury or death, and damage to property and facilities.

• Fuel is highly flammable and dangerous. Fuel line spills and leakage can cause serious injury or death, and damage to equipment. Always refer to the “Quick Release Connector Removal/Installation (fuel system)” before performing the fuel hose installation, and execute the “Fuel Leakage Inspection” after installation. (See QUICK RELEASE CONNECTOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0].) (See AFTER SERVICE PRECAUTION [SKYACTIV-G 2.0].)

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 material.

Item (definition)

Unit/Condition

Definition

Condition/Specification (Reference)

FUEL_PRES

KPa , mBar , psi, in H20

Fuel pressure input from fuel pressure sensor

• Displays fuel pressure

V

Fuel pressure sensor voltage

Ignition switched ON (engine off)

• Fuel pressure is approx. 3.6 MPa {37 kgf/cm², 522 psi}: Approx. 1.01 V (ECT is 92 °C {198 °F})

Idle (after warm up)

• Fuel pressure is approx. 3.45 MPa {35.2 kgf/cm², 500 psi}: Approx. 1 V (ECT is 92 °C {198 °F})

Racing (Engine speed is 2,000 rpm)

• Fuel pressure is approx. 3.21 MPa {32.7 kgf/cm², 466 psi}: Approx. 0.96 V (ECT is 86 °C {187 °F})

Racing (Engine speed is 4,000 rpm)

• Fuel pressure is approx. 5.59 MPa {57.0 kgf/cm², 811 psi}: Approx. 1.29 V (ECT is 84 °C {183 °F})

LOAD

%

Ratio of actual amount of intake air to the maximum air charging amount (mass volume) of cylinder

• Idle (after warm up): Approx. 27.05% (ECT is 91 °C {196 °F})

• Racing (engine speed is 2,000 rpm): Approx. 16.86% (ECT is 89 °C {192 °F})

• Racing (engine speed is 4,000 rpm): Approx. 17.64% (ECT is 87 °C {189 °F})

STEP

INSPECTION

RESULTS

ACTION

1

• Retrieve any DTCs using the M-MDS.

  (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [PCM (SKYACTIV-G 2.0)].)

No

Go to the next step.

2

• Verify that the drive mode is completed.

• Is the drive mode completed?

Yes

Go to the next step.

No

Perform the Drive Mode.

(See OBD-II DRIVE MODE [PCM (SKYACTIV-G 2.0)].)

3

• Can malfunction symptoms other than “NO.15 EMISSION COMPLIANCE” be verified?

  (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.0].)

Yes

Go to the applicable symptom troubleshooting.

(See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.0].)

No

Go to the next step.

4

• Verify CO and HC concentration.

• Is the CO or HC concentration excessive?

Yes

Go to Step 6.

NOTE:

• If the HC concentration is normal and the CO concentration is excessive, a rich A/F can be considered the cause.

• If the CO concentration is normal and the HC concentration is excessive, a A/F lean can be considered the cause.

• If the CO and HC concentration is excessive, incomplete combustion or a rich A/F can be considered the cause.

No

Go to the next step.

5

• Verify NOx concentration.

• Is the NOx concentration excessive?

Yes

Go to the next step.

No

Symptom troubleshooting is completed.

6

• Inspect the ignition timing.

  (See ENGINE TUNE-UP [SKYACTIV-G 2.0].)

• Is there any malfunction?

Yes

Inspect the following:

• Spark plug

  (See SPARK PLUG INSPECTION [SKYACTIV-G 2.0].)

• Ignition coil/ion sensor No.1

  (See IGNITION COIL INSPECTION [SKYACTIV-G 2.0].)

  (See ION SENSOR INSPECTION [SKYACTIV-G 2.0].)

• Ignition coil/ion sensor No.2

  (See IGNITION COIL INSPECTION [SKYACTIV-G 2.0].)

  (See ION SENSOR INSPECTION [SKYACTIV-G 2.0].)

• Ignition coil/ion sensor No.3

  (See IGNITION COIL INSPECTION [SKYACTIV-G 2.0].)

  (See ION SENSOR INSPECTION [SKYACTIV-G 2.0].)

• Ignition coil/ion sensor No.4

  (See IGNITION COIL INSPECTION [SKYACTIV-G 2.0].)

  (See ION SENSOR INSPECTION [SKYACTIV-G 2.0].)

• If there is any malfunction:

• Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

• If there is no malfunction:

• Go to Step 18.

No

Go to the next step.

7

• Perform the Purge Control System Inspection.

  (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [SKYACTIV-G 2.0].)

• Does the purge solenoid valve work properly?

Yes

Go to the next step.

No

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

8

• Start the engine and warm it up completely.

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

  (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)].)

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

Yes

Go to the next step.

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 2.0].)

• Fuel pressure sensor

  (See FUEL PRESSURE SENSOR INSPECTION [SKYACTIV-G 2.0].)

• High pressure fuel pump

  (See HIGH PRESSURE FUEL PUMP INSPECTION [SKYACTIV-G 2.0].)

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

• Inspect the following:

• Fuel line and fuel injector restriction

• Fuel pressure sensor

  (See FUEL PRESSURE SENSOR INSPECTION [SKYACTIV-G 2.0].)

• High pressure fuel pump (Relief valve clogged)

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

9

• Inspect for leakage in intake-air system.

• Is there any leakage?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

No

Go to the next step.

10

• Inspect for restriction in the ventilation hose.

• Is there any restriction?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

No

Go to the next step.

11

• Inspect the charcoal canister.

  (See CHARCOAL CANISTER INSPECTION [SKYACTIV-G 2.0].)

• Is the charcoal canister damaged?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

(See CHARCOAL CANISTER REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)

No

Go to the next step.

12

• Inspect the engine coolant level.

  (See ENGINE COOLANT LEVEL INSPECTION [SKYACTIV-G 2.0].)

• Is there any malfunction?

Yes

Add engine coolant and verify that there is no engine coolant leakage.

(See ENGINE COOLANT REPLACEMENT [SKYACTIV-G 2.0].)

(See ENGINE COOLANT LEAKAGE INSPECTION [SKYACTIV-G 2.0].)

• If there is any malfunction:

• Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

• If there is no malfunction:

• Go to Step 18.

No

Go to the next step.

13

• Verify carbon accumulation condition in combustion chamber.

• Has carbon accumulated?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

No

Go to the next step.

14

• Measure the compression pressure for each cylinder.

  (See COMPRESSION INSPECTION [SKYACTIV-G 2.0].)

• Are compression pressures within specification?

Yes

Go to the next step.

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

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

15

• Inspect for restriction in the TWC.

• Is there any restriction?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

(See EXHAUST SYSTEM REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)

No

Go to the next step.

16

• Visually inspect for exhaust gas leakage from the exhaust system.

• Is there any malfunction?

Yes

Repair or replace the malfunctioning part according to the inspection results, then go to Step 18.

No

Go to the next step.

17

• Inspect the PCV valve.

  (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION [SKYACTIV-G 2.0].)

• Is there any malfunction?

Yes

Replace the PCV valve, then go to the next step.

(See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)

No

Go to the next step.

18

• Measure CO, HC, and NOx concentration again.

• Is CO, HC, and NOx concentration within specification?

Yes

Symptom troubleshooting is completed.

No

Repeat the inspection from Step 1.