NO.15 EMISSION COMPLIANCE [WITH WU-TWC]


15	EMISSION COMPLIANCE
DESCRIPTION	Fails the 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 • EGR valve malfunction (ZJ) • Exhaust system clogging • Fuel tank ventilation system malfunction • Charcoal canister damage • Air cleaner element clogging or restriction • Throttle body malfunction • Spark leakage from high-tension leads • Improper air/fuel mixture ratio control operation • Catalytic 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 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 REPAIR PROCEDURE" and "AFTER REPAIR PROCEDURE" described in this manual. Caution • If there is foreign material on the connecting area of the quick release connector, it might damage the connector or the fuel pipe. To prevent this, disconnect the connector and clean the connecting area before connecting.


STEP	INSPECTION	RESULTS	ACTION
1	Inspect 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 dirt Are all items normal?	Yes	Go to the next step.
1		No	Service if necessary. Repeat Step 1.
2	Connect the WDS or equivalent to the DLC-2. Retrieve any continuous memory, KOEO and KOER DTCs. (See KOEO/KOER SELF-TEST.) Are there any DTCs displayed?	Yes	DTC is displayed: Go to the appropriate DTC test.
2		No	No DTC is displayed: Go to the next step.
3	Is any other driveability concern present?	Yes	Go to the appropriate symptom troubleshooting.
3	Is any other driveability concern present?	No	Go to the next step.
4	Connect the WDS or equivalent to the DLC-2. Access the ECT PID. Warm up the engine and idle it. Verify that the ECT PID is correct. Is the ECT PID correct?	Yes	Go to the next step.
4		No	Inspect for coolant leakage, cooling fan and condenser fan operations, or thermostat operation.
5	Carry out a spark test. Is a strong blue spark visible at each cylinder?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning part according to spark test results.
6	Install a fuel pressure gauge between fuel pipe and the fuel distributor. Start the engine and idle it. Measure the fuel line pressure at idle. Is the fuel line pressure correct at idle?	Yes	Go to the next step.
6		No	Zero or low: Inspect the fuel pump relay and the fuel pump related circuits. Inspect for fuel leakage inside the pressure regulator. Inspect for a clogged main fuel line. High: Inspect the pressure regulator for high pressure cause. Inspect for a clogged fuel return line. Inspect the vacuum hose to the pressure regulator.
7	Remove and shake the PCV valve. Does the PCV valve rattle?	Yes	Go to the next step.
7	Remove and shake the PCV valve. Does the PCV valve rattle?	No	Replace the PCV valve.
8	Inspect the fuel saturation inside the charcoal canister. Is an excess amount of liquid fuel present in the canister?	Yes	Replace the charcoal canister.
8		No	Inspect the fuel tank vent system. Then, go to the next step.
9	Visually inspect the exhaust system part. Is there any deformed exhaust system part?	Yes	Replace the suspected part.
9		No	With EGR system: Inspect the EGR system. • If there is no malfunction, inspect the three-way catalytic converter. Without EGR system: Inspect the three-way catalytic converter.
10	Verify the test results. • If normal, return to the diagnostic index to service any additional symptoms. • If the malfunction remains, inspect related Service information and perform repair or diagnosis. - If the vehicle is repaired, the troubleshooting is completed. - If the vehicle is not repaired or additional diagnostic information is not available, replace the PCM.