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.
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
Connect the M-MDS to the DLC-2.
Perform the KOEO/KOER self test.
Are any continuous memory DTCs present?
Yes
Go to the appropriate DTC inspection.
No
Go to the next step.
3
Is any other drivability concern present?
Yes
Go to the appropriate symptom troubleshooting.
No
Go to the next step.
4
Connect the M-MDS to the DLC-2.
Perform the PID/DATA Monitor and Record Procedure and access the ECT PID.
Warm-up the engine and idle it.
Is the ECT PID correct?
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
Connect the M-MDS to the DLC-2.
Warm up the engine and idle it.
Perform the PID/DATA Monitor and Record Procedure and access the O2S11 PID.
Is the O2S11 PID normal?
•  Less than 1 mA when the accelerator pedal is suddenly depressed: rich condition
•  More than 1 mA during fuel cut: lean condition
Yes
Go to the next step.
No
Inspect the A/F sensor, related wiring harness, connector and terminals.
Repair or replace the malfunctioning part according to the inspection results, if necessary.
Go to the next step.
6
Connect the M-MDS to the DLC-2.
Warm up the engine and idle it.
Perform the PID/DATA Monitor and Record Procedure and access the O2S12 PID.
Is the O2S12 PID normal?
•  More than 0.45 V when the accelerator pedal is suddenly depressed: rich condition
•  Less than 0.45 V during fuel cut: lean condition
Yes
Go to the next step.
No
Inspect the following:
•  Exhaust gas leakage at from A/F sensor to HO2S
•  HO2S, related wiring harness, connector and terminals
If there is a malfunction:
•  Repair or replace the malfunctioning part according to the inspection results.
If there is no malfunction:
•  Go to the next step.
7
Perform the Spark Test.
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?
Yes
Go to the next step.
No
Low:
•  Inspect for clogged fuel line.
•  If normal:
―  Replace the fuel pump unit.
High:
•  Replace the fuel pump unit.
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.
No
Inspect the fuel tank vent system.
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.
Is there any malfunction?
Yes
Replace the TWC.
No
Go to the next step.
12
Perform the EGR Control System Inspection.
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.
13
Verify test results.
•  If normal, return to diagnostic index to service any additional symptoms.
•  If malfunction remains, inspect related Service information perform repair or diagnosis.
―  If vehicle repaired, troubleshooting completed.
―  If vehicle not repaired or additional diagnostic information not available, replace the PCM.