P0448

P0448 EVAP Canister Vent Control Valve

Component Description

The EVAP canister vent control valve (1) is located on the EVAP canister (4) and is used to seal the canister vent.

- EVAP control system pressure sensor (2)





- Drain filter (3)
- : Vehicle front

This solenoid valve responds to signals from the ECM. When the ECM sends an ON signal, the coil in the solenoid valve is energized. A plunger will then move to seal the canister vent. The ability to seal the vent is necessary for the on board diagnosis of other evaporative emission control system components.





This solenoid valve is used only for diagnosis, and usually remains opened.

When the vent is closed, under normal purge conditions, the evaporative emission control system is depressurized and allows "EVAP Control System" diagnoses.

On Board Diagnosis Logic






DTC Confirmation Procedure

NOTE:

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

with SDT

1) Turn ignition switch ON and wait at least 5 seconds.
2) Turn ignition switch OFF and wait at least 10 seconds.
3) Start engine and let it idle for at least 1 minute.
4) Repeat next procedures 3 times.
a) Increase the engine speed between 3,000 and 3,500 rpm and maintain that speed for 2 minutes and 50 seconds to 3 minutes.
Never exceed 3 minutes.
b) Fully released accelerator pedal and keep engine idle for about 5 seconds.
5) Check 1st trip DTC.
6) If 1st trip DTC is detected, go to "Diagnosis Procedure".

If 1st trip DTC is not detected, go to the next step.
7) Repeat next procedure 20 times.
a) Quickly increase the engine speed between 4,000 and 4,500 rpm and maintain that speed for 25 to 30 seconds.
b) Fully released accelerator pedal and keep engine idle for at least 35 seconds.





8) Check 1st trip DTC.
9) If 1st trip DTC is detected, go to "Diagnosis Procedure".

with GST

Follow the procedure "WITH SDT" above.

Diagnosis Procedure

1. CHECK RUBBER TUBE

1 Turn ignition switch OFF.
2 Disconnect rubber tube connected to EVAP canister vent control valve (1).





- EVAP control system pressure sensor (2)
- Drain filter (3)
- EVAP canister (4)
-: Vehicle front
3 Check the rubber tube for clogging.

OK or NG
OK
GO TO 2.
NG
Clean rubber tube using an air blower.

2. CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to "Component Inspection".

OK or NG
OK
GO TO 3.
NG
Replace EVAP canister vent control valve. Refer to [EVAP Canister: Removal and Installation] Service and Repair.

3. CHECK IF EVAP CANISTER IS SATURATED WITH WATER

1 Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.
2 Does water drain from the EVAP canister?






Yes or No
Yes
GO TO 4.
No
GO TO 6.

4. CHECK EVAP CANISTER

Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor attached.

The weight should be less than 2.0 kg (4.4 lb).

OK or NG
OK
GO TO 6.
NG
GO TO 5.

5. DETECT MALFUNCTIONING PART

Check the following.
- EVAP canister for damage
- EVAP hose between EVAP canister and vehicle frame for clogging or poor connection


Repair hose or replace EVAP canister.

6. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR

1 Disconnect EVAP control system pressure sensor (2) harness connector.





- EVAP canister vent control valve (1)
- Drain filter (3)
- EVAP canister (4)
-: Vehicle front
2 Check that water is not inside connectors.

OK or NG
OK
GO TO 7.
NG
Replace EVAP control system pressure sensor. Refer to [EVAP Canister: Removal and Installation] Service and Repair.

7. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to [P0453 EVAP Control System Pressure Sensor] P0453.

OK or NG
OK
GO TO 8.
NG
Replace EVAP control system pressure sensor. Refer to [EVAP Canister: Removal and Installation] Service and Repair.

8. CHECK INTERMITTENT INCIDENT

Refer to [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.


INSPECTION END

Component Inspection

EVAP Canister Vent Control Valve

With SDT

1) Remove EVAP canister vent control valve from EVAP canister.
2) Check portion B of EVAP canister vent control valve for being rusted.





If NG, replace EVAP canister vent control valve.

If OK, go to next step.
3) Reconnect harness connectors disconnected.
4) Turn ignition switch ON.
5) Perform "VENT CONTROL/V" in "Active test" mode.
6) Check air passage continuity and operation delay time.






Operation takes less than 1 second.

Make sure new O-ring is installed properly.

If NG, replace EVAP canister vent control valve.

If OK, go to next step.
7) Clean the air passage (Portion A to B) of EVAP canister vent control valve using an air blower.
8) Perform step 6 again.

Without SDT

9) Remove EVAP canister vent control valve from EVAP canister.
10) Check portion B of EVAP canister vent control valve for being rusted.





11) Check air passage continuity and operation delay time under the following conditions.











Operation takes less than 1 second.

Make sure new O-ring is installed properly.

If NG, replace EVAP canister vent control valve.

If OK, go to next step.
12) Clean the air passage (Portion A to B) of EVAP canister vent control valve using an air blower.
13) Perform step 3 again.