Confirmation Procedure
- CHECK DTC PRIORITY
If DTC P21F4 is displayed with DTC P0171, first perform the trouble diagnosis for DTC P0171.
Is applicable DTC detected?
YES
Perform diagnosis of applicable. Refer to DTC Description .
NO
GO TO 2.
- PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
GO TO 3.
- PERFORM DTC CONFIRMATION PROCEDURE-1
- Clear the mixture ratio self-learning value. Refer to Work Procedure .
- Start engine.
Is it difficult to start engine?
YES
GO TO 4.
NO
GO TO 5.
- RESTART ENGINE
If it is difficult to start engine, the fuel injection system has a malfunction, too.
Crank engine while depressing accelerator pedal.
NOTE: When depressing accelerator pedal three fourths (3/4) or more, the control system does not start the engine. Do not depress accelerator pedal too much.Does engine start?
YES
Proceed to Diagnosis Procedure .
NO
Check exhaust and intake air leakage visually.
- PERFORM DTC CONFIRMATION PROCEDURE-2
- Keep engine idle for at least 10 minutes.
- Check 1st trip DTC.
Is 1st trip DTC detected?
YES
Proceed to Diagnosis Procedure .
NO
GO TO 6.
- PERFORM DTC CONFIRMATION PROCEDURE-3
- Turn ignition switch OFF and wait at least 10 seconds.
- Start engine and Maintain the following conditions for at least 10 consecutive minutes. Hold the accelerator pedal as steady as possible.
Vehicle speed
50 - 100 km/h (31 - 62 MPH)
CAUTION: Always drive vehicle at a safe speed. - Check 1st trip DTC.
Is 1st trip DTC detected?
YES
Proceed to Diagnosis Procedure .
NO
To check malfunction symptom before repair: Refer to Intermittent Incident .
NO
Confirmation after repair: INSPECTION END