NO.15 EMISSION COMPLIANCE [L8, LF]


id0103a0802100

15

EMISSION COMPLIANCE

DESCRIPTION

Fails 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
• Exhaust system clogging
• Fuel tank ventilation system malfunction
• Charcoal canister damage
• Air cleaner element clogging or restriction
• Throttle body malfunction
• Erratic signal to ignition coil
• Improper air/fuel mixture ratio control operation
• Bend or open circuit A/F sensor or HO2S wiring harness
• Catalyst 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 fuel system diagnosis and repair procedures. Read following warnings before performing 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 "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual.
(See BEFORE SERVICE PRECAUTION [L8, LF].)
(See AFTER SERVICE PRECAUTION [L8, LF].)
Caution
• Disconnecting/connecting quick release connector without cleaning it may possibly cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

Diagnostic procedure

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 dirtiness
Are all items normal?
Yes
Go to the next step.
No
Service if necessary.
Repeat Step 1.
2
Connect the M-MDS to the DLC-2.
Retrieve any continuous memory, KOEO and KOER DTCs using M-MDS.
Are there any DTCs displayed?
Yes

DTC is displayed:

Go to the appropriate DTC inspection.
No

No DTC is displayed:

Go to the next step.
3
Is any other driveability concern present?
Yes
Go to appropriate symptom troubleshooting.
No
Go to the next step.
4
Connect the M-MDS to the DLC-2.
Access ECT PID.
Warm up the engine and idle it.
Verify ECT PID is correct.
Is ECT PID correct?
Yes
Go to the next step.
No
Inspect for coolant leakage, cooling fan and thermostat operation.
5
Connect the M-MDS to the DLC-2.
Warm up the engine and idle it.
Access O2S11 PID.
Is 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 and repair or replace the A/F sensor, wiring harness, connector or terminal, then go to the next step.
6
Perform the spark test.
(See Spark Test.)
Is strong blue spark visible at each cylinder?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to spark test result.
7
Install fuel pressure gauge between the fuel pipe and the fuel distributor.
Start the engine and idle it.
Measure fuel line pressure during idle.
Is fuel line pressure correct during idle?
Yes
Go to the next step.
No

Low:

Inspect the fuel line for clogging.
• If normal, replace fuel pump unit.

High:

Replace the fuel pump unit.
8
Remove and shake the PCV valve.
Does the PCV valve rattle?
Yes
Go to the next step.
No
Replace the PCV valve.
9
Inspect for fuel saturation inside the charcoal canister.
Is excess amount of liquid fuel present in 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 deformed exhaust system part?
Yes
Replace the part.
No
Go to the next step.
11
Inspect the three way catalytic converter.
Is the three way catalytic converter normal?
Yes
Inspect the EGR system.
No
Replace the three way catalytic converter.
12
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.
(See PCM REMOVAL/INSTALLATION [L8, LF].)