NO.15 EMISSION COMPLIANCE [ZJ, ZY]

id0103b0802100

15

EMISSION COMPLIANCE

DESCRIPTION

•  Fails emissions test.

POSSIBLE CAUSE

•  Electrical connector disconnection

•  Intake-air system clogging or restriction

•  Air cleaner element clogging or restriction

•  Vacuum lines leakage or blockage

•  Continuous memory DTC is stored

•  Cooling system malfunction

•  Improper operation of air/fuel mixture ratio control

•  Bend or open circuit A/F sensor or HO2S wiring harness

•  Spark plug malfunction

•  Inadequate fuel pressure

•  Charcoal canister damage

•  Fuel tank ventilation system malfunction

•  Restriction in exhaust system

•  TWC malfunction

•  Improper operation of EGR control system

•  PCV valve malfunction

•  Valve timing malfunction

•  PCM malfunction

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.

•  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 the “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [ZJ, ZY].) (See AFTER SERVICE PRECAUTION [ZJ, ZY].)

Caution

•  If there is foreign material on the connecting area of the quick release connector, it might damage the connector or fuel pipe. To prevent this, disconnect the connector and clean the connecting area before connecting.

15	EMISSION COMPLIANCE
DESCRIPTION	• Fails emissions test.
POSSIBLE CAUSE	• Electrical connector disconnection • Intake-air system clogging or restriction • Air cleaner element clogging or restriction • Vacuum lines leakage or blockage • Continuous memory DTC is stored • Cooling system malfunction • Improper operation of air/fuel mixture ratio control • Bend or open circuit A/F sensor or HO2S wiring harness • Spark plug malfunction • Inadequate fuel pressure • Charcoal canister damage • Fuel tank ventilation system malfunction • Restriction in exhaust system • TWC malfunction • Improper operation of EGR control system • PCV valve malfunction • Valve timing malfunction • PCM malfunction 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. • 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 the “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION” described in this manual. (See BEFORE SERVICE PRECAUTION [ZJ, ZY].) (See AFTER SERVICE PRECAUTION [ZJ, ZY].) Caution • If there is foreign material on the connecting area of the quick release connector, it might damage the connector or fuel pipe. To prevent this, disconnect the connector and clean the connecting area before connecting.

Diagnostic procedure

STEP	INSPECTION	ACTION
1	Inspect the following: • Electrical connections • Intake-air system and air cleaner element concerns: obstructions, leakage or dirtiness • Proper maintenance schedule followed • Vacuum lines for leakage or blockage Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Repeat Step 1.
		No	Go to the next step.
2	Perform the KOEO and KOER self test. (See KOEO/KOER SELF TEST [ZJ, ZY].) Are any continuous memory DTCs present?	Yes	Go to the appropriate DTC inspection. (See DTC TABLE [ZJ, ZY].)
		No	Go to the next step.
3	Is any other drivability concern present?	Yes	Go to the appropriate symptom troubleshooting. (See SYMPTOM DIAGNOSTIC INDEX [ZJ, ZY].)
		No	Go to the next step.
4	Perform the PID/DATA Monitor and Record Procedure and access the ECT PID. (See ON-BOARD DIAGNOSTIC TEST [ZJ, ZY].) Warm up the engine and idle it. Is the ECT PID correct? (See PCM INSPECTION [ZJ, ZY].)	Yes	Go to the next step.
		No	Inspect for coolant leakage, cooling fan and thermostat operation. Repair or replace the malfunctioning part according to the inspection results.
5	Inspect the A/F sensor. (See AIR FUEL RATIO (A/F) SENSOR INSPECTION [ZJ, ZY].) Is there any malfunction?	Yes	Inspect for followings: • Exhaust gas leakage between exhaust manifold and A/F sensor • Loose installation of A/F sensor ― If there is no malfunction: • Replace the A/F sensor. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [ZJ, ZY].) ― If there is a malfunction: • Repair or replace the malfunctioning part according to the inspection results.
		No	Go to the next step.
6	Inspect the HO2S. (See HEATED OXYGEN SENSOR (HO2S) INSPECTION [ZJ, ZY].) Is there any malfunction?	Yes	Inspect for followings: • Exhaust gas leakage between A/F sensor and HO2S • Loose installation of HO2S ― If there is no malfunction: • Replace the HO2S. (See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [ZJ, ZY].) ― If there is a malfunction: • Repair or replace the malfunctioning part according to the inspection results.
		No	Go to the next step.
7	Perform the Spark Test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [ZJ, ZY].) Is the 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.
8	Install the fuel pressure gauge between the fuel pipe and the fuel distributor. Start the engine and idle it. Measure the fuel line pressure during idle. Is the fuel line pressure correct during idle? (See FUEL LINE PRESSURE INSPECTION [ZJ, ZY].)	Yes	Go to the next step.
		No	Low: • Inspect for clogged fuel line. • If normal: ― Replace the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [ZJ, ZY].) High: • Replace the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [ZJ, ZY].)
9	Inspect inside charcoal canister for fuel saturation. Is the excess amount of liquid fuel present in the charcoal canister?	Yes	Replace the charcoal canister. (See CHARCOAL CANISTER REMOVAL/INSTALLATION [ZJ, ZY].)
		No	Inspect the fuel tank vent system. (See FUEL TANK INSPECTION [ZJ, ZY].) Repair or replace the malfunctioning part according to the inspection results, then go to the next step.
10	Visually inspect the exhaust system part. Is there any defective exhaust system part?	Yes	Repair or replace the malfunctioning part according to the inspection results.
		No	Go to the next step.
11	Inspect the TWC. (See EXHAUST SYSTEM INSPECTION [ZJ, ZY].) Is there any malfunction?	Yes	Replace the TWC. (See EXHAUST SYSTEM REMOVAL/INSTALLATION [ZJ, ZY].)
		No	Go to the next step.
12	Perform the EGR Control System Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [ZJ, ZY].) Is there any malfunction?	Yes	Inspect the valve timing. Repair or replace the malfunctioning part according to the inspection results.
		No	Replace the PCV valve and the oil separator as a single unit. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [ZJ, ZY].)
13	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [ZJ, ZY].) • If the malfunction remains, inspect the related Service Information and perform the repair or diagnosis. ― If the vehicle is repaired, troubleshooting is completed. ― If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM. (See PCM REMOVAL/INSTALLATION [ZJ, ZY].)