P0451

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

Component Description






The EVAP control system pressure sensor (2) detects pressure in the purge line. The sensor output voltage to the ECM increases as pressure increases.
- EVAP canister vent control valve (3)
- EVAP canister (4)
- Drain filter (5)
-White arrow indicates : Vehicle front







On Board Diagnosis Logic

If DTC P0451 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643.







DTC Confirmation Procedure


DTC CONFIRMATION PROCEDURE

NOTE:
Never remove fuel filler cap during DTC confirmation procedure.

1. PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
1.Turn ignition switch OFF and wait at least 10 seconds.
2.Turn ignition switch ON.
3.Turn ignition switch OFF and wait at least 10 seconds.
With CONSULT-GO TO 2.
Without CONSULT-GO TO 5.

2. PERFORM DTC CONFIRMATION PROCEDURE-1

With CONSULT
1.Start engine and let it idle for least 40 seconds.
NOTE:
Do not depress accelerator pedal even slightly.
2.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Proceed to .
NO- GO TO 3.

3. PERFORM DTC CONFIRMATION PROCEDURE-2

With CONSULT
1.Select "EVAP DIAG READY" in "DATA MONITOR" mode of "ENGINE".
2.Let it idle until "OFF" of "EVAP DIAG READY" changes to "ON".
NOTE:
It will take at most 2 hours until "OFF" of "EVAP DIAG READY" changes to "ON".
3.Turn ignition switch OFF and wait at least 90 minutes.
NOTE:
Never turn ignition switch ON during 90 minutes.
4.Turn ignition switch ON.
5.Select "EVAP LEAK DIAG" in "DATA MONITOR" mode of "ENGINE".
6.Check that "EVAP LEAK DIAG" indication.
Which is displayed on CONSULT?
CMPLT- GO TO 4.
YET- 1.Perform DTC CONFIRMATION PROCEDURE again.
2.GO TO 1.

4. PERFORM DTC CONFIRMATION PROCEDURE-3

With CONSULT
Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Proceed to .
NO- INSPECTION END

5. PERFORM DTC CONFIRMATION PROCEDURE-4

With GST
1.Start engine and let it idle for least 40 seconds.
NOTE:
Do not depress accelerator pedal even slightly.
2.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Proceed to .
NO- GO TO 6.

6. PERFORM DTC CONFIRMATION PROCEDURE-5

With GST
1.Let it idle for at least 2 hours.
2.Turn ignition switch OFF and wait at least 90 minutes.
NOTE:
Never turn ignition switch ON during 90 minutes.
3.Turn ignition switch ON.
4.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Proceed to .
NO- INSPECTION END


Diagnosis Procedure


1. CHECK GROUND CONNECTIONS

1.Turn ignition switch OFF.
2.Loosen and retighten three ground screws on the body. Power Supply And Ground Circuit.





OK or NG
OK- GO TO 2.
NG- Repair or replace ground connections.

2. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR FOR WATER






1.Disconnect EVAP control system pressure sensor (2) harness connector.
-Fuel filler pipe (1)
-EVAP canister vent control valve (3)
-EVAP canister (4)
-Drain filter (5)
-White arrow indicates : Vehicle front
2.Check sensor harness connector for water.
Water should not exist.
OK or NG
OK- GO TO 3.
NG- Repair or replace harness connector.

3. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

.
OK or NG
OK- GO TO 4.
NG- Replace EVAP control system pressure sensor. Service and Repair.

4. CHECK INTERMITTENT INCIDENT

Intermittent Incident.
-INSPECTION END


Component Inspection


EVAP CONTROL SYSTEM PRESSURE SENSOR

1.Remove EVAP control system pressure sensor with its harness connector.
Do not reuse the O-ring, replace it with a new one.
2.Install a vacuum pump to EVAP control system pressure sensor.





3.Turn ignition switch ON and check output voltage between ECM
terminal 32 and ground under the following conditions.






CAUTION:
- Always calibrate the vacuum pump gauge when using it.
- Never apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or pressure over 101.3 kPa (1.033 kg/cm2, 14.69 psi).
4.If NG, replace EVAP control system pressure sensor.