Inspection Procedure 16: Odour, White Smoke, Black Smoke and High-concentration of CO/HC during Idling

COMMENTS ON TROUBLE SYMPTOM

The failure could possibly be caused by the improper air-fuel ratio, deteriorated catalyst, failed ignition system, defective fuel system, faulty compression pressure and so on.

PROBABLE CAUSES

Failed air-fuel ratio control system
Failed ignition system
Failed fuel system
Failed exhaust system
Improper compression pressure
Deteriorated catalyst
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q. Is diagnosis code stored?

	Inspection chart for diagnosis code (Refer to ).

	Go to Step 2.

STEP 2. Check injector for operating sound.

Injector check (Refer to ).

Q. Is operating sound audible?

	Go to Step 3.

	Check the injector system of the defective cylinder. (Refer to P0261: No.1 injector circuit low input ). (Refer to P0262 No.1 injector circuit high input ). (Refer to P0264 No.2 injector circuit low input ). (Refer to P0265 No.2 injector circuit high input ). (Refer to P0267 No.3 injector circuit low input ). (Refer to P0268 No.3 injector circuit high input ).

STEP 3. Check ignition timing.

Check ignition timing (Refer to GROUP 11A - On-vehicle Service - Ignition Timing Check ).

Q. Is the check result normal?

	Go to Step 4.

	Check Inspection Procedure - ignition timing deviation (Refer to ).

STEP 4. M.U.T.-III data list

Data list reference table (Refer to ).

Item 5: Intake air temperature sensor
Item 6: Engine coolant temperature sensor
Item 8: Manifold absolute pressure sensor

Q. Are the check results normal?

	Go to Step 5.

	Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value. Inspection chart for diagnosis code (Refer to ).

STEP 5. Check exhaust leak from exhaust manifold.

Q. Is the check result normal?

	Go to Step 6.

	Repair.

STEP 6. Check throttle body (throttle valve portion) contamination.

Q. Is the check result normal?

	Go to Step 7.

	Throttle body (throttle valve area) cleaning (Refer to ).

STEP 7. M.U.T.-III data list

Data list reference table (Refer to ).

Item AC: Oxygen sensor (front)
Item AD: Oxygen sensor (rear)

Q. Are the check results normal?

	Go to Step 8.

	Perform the diagnosis code classified check procedure for the sensor that has shown an abnormal data value. Inspection chart for diagnosis code (Refer to ).

STEP 8. Check purge control solenoid valve itself.

Check purge control solenoid valve itself (Refer to GROUP 17- Emission Control - Evaporative Emission Control System - Purge Control Solenoid Valve Check ).

Q. Is the check result normal?

	Go to Step 9.

	Replace the purge control solenoid valve.

STEP 9. Fuel pressure measurement.

Fuel pressure test (Refer to ).

Q. Is the check result normal?

	Go to Step 10.

	Repair.

STEP 10. Check positive crankcase ventilation valve itself.

Check positive crankcase ventilation valve itself (Refer to GROUP 17 - Emission Control - Crankcase Emission Control System - Positive Crankcase Ventilation Valve Check ).

Q. Is the check result normal?

	Go to Step 11.

	Replace the positive crankcase ventilation valve.

STEP 11. Check spark plug.

Check spark plug (Refer to GROUP 16 - Ignition System - On-vehicle service - Spark Plug Check and Cleaning ).

Q. Is the check result normal?

	Go to Step 12.

	Replace the spark plug.

STEP 12. Check compression pressure.

Check the compression pressure (Refer to GROUP 11A - On-vehicle Service - Compression Pressure Check ).

Q. Is the check result normal?

	Go to Step 13.

	Repair.

STEP 13. Check injector for spray condition.

Injector check (Refer to ).

Q. Is the check result normal?

	Go to Step 14.

	Replace the injector.

STEP 14. Replace the catalytic converter.

After the replacing the catalytic converter, re-check the trouble symptoms.

Q. Does the trouble symptom persist?

	Replace the engine-ECU.

	Check end.