Nissan Altima L32. Manual - part 552

P0448 EVAP CANISTER VENT CONTROL VALVE

EC-1329

< COMPONENT DIAGNOSIS >

[VQ35DE]

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Fully released accelerator pedal and keep engine idle for at least 35 seconds.

7. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-1329, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000004362171

1.

CHECK RUBBER TUBE

1. Turn ignition switch OFF.

2. Disconnect rubber tube connected to EVAP canister vent control valve.

3. Check the rubber tube for clogging.
Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Clean rubber tube using an air blower.

2.

CHECK EVAP CANISTER VENT CONTROL VALVE

Refer to 

EC-1330, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Replace EVAP canister vent control valve.

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. Check if water will drain from the EVAP canister.
Does water drain from the EVAP canister?

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 2.1 kg (4.6 lb).
Is the inspection result normal?

YES

>> GO TO 6.

NO

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.

• EVAP canister for damage

JMBIA1516GB

PBIB1213E

EC-1330

< COMPONENT DIAGNOSIS >

[VQ35DE]

P0448 EVAP CANISTER VENT CONTROL VALVE

• 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 harness connector.

2. Check that water is not inside connectors.
Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace EVAP control system pressure sensor.

7.

CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Refer to 

EC-1334, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Replace EVAP control system pressure sensor.

8.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000004362172

1.

CHECK EVAP CANISTER VENT CONTROL VALVE-I

1. Remove EVAP canister vent control valve from EVAP canister.

2. Check portion (A) of EVAP canister vent control valve for rust.
Is it rusted?

YES

>> Replace EVAP canister vent control valve.

NO

>> GO TO 2.

2.

CHECK EVAP CANISTER VENT CONTROL VALVE-II

With CONSULT-III

1. Reconnect harness connectors disconnected.

2. Turn ignition switch ON.

3. Perform “VENT CONTROL/V” in “ACTIVE TEST” mode.

4. Check air passage continuity and operation delay time.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Without CONSULT-III

1. Disconnect EVAP canister vent control valve harness connector.

2. Check air passage continuity and operation delay time under the

following conditions.

Check that new O-ring is installed properly.

JMBIA0168ZZ

Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

Not existed

OFF

Existed

JMBIA0169ZZ

P0448 EVAP CANISTER VENT CONTROL VALVE

EC-1331

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Operation takes less than 1 second.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 3.

3.

CHECK EVAP CANISTER VENT CONTROL VALVE-III

With CONSULT-III

1. Clean the air passage [portion (A) to (B)] of EVAP canister vent control valve using an air blower.

2. Perform “VENT CONTROL/V” in “ACTIVE TEST” mode.

3. Check air passage continuity and operation delay time.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Without CONSULT-III

1. Clean the air passage [portion (A) to (B)] of EVAP canister vent

control valve using an air blower.

2. Check air passage continuity and operation delay time under the

following conditions.

Check that new O-ring is installed properly.

Operation takes less than 1 second.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace EVAP canister vent control valve

Condition

Air passage continuity between (A) and (B)

12 V direct current supply between
 terminals 1 and 2

Not existed

OFF

Existed

Condition VENT CONTROL/V

Air passage continuity between (A) and (B)

ON

No

OFF

Yes

Condition

Air passage continuity between (A) and (B)

12 V direct current supply between
 terminals (1) and (2)

No

OFF

Yes

JMBIA0169ZZ

EC-1332

< COMPONENT DIAGNOSIS >

[VQ35DE]

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR

Description

INFOID:0000000004362173

The EVAP control system pressure sensor detects pressure in the

purge line. The sensor output voltage to the ECM increases as pres-

sure increases.

DTC Logic

INFOID:0000000004362174

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing 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.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and wait at least 40 seconds.

NOTE:

Do not depress accelerator pedal even slightly.

2. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-1332, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000004362175

1.

CHECK GROUND CONNECTION

1. Turn ignition switch OFF.

PBIB3370E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0451

EVAP control system 
pressure sensor perfor-
mance

ECM detects a sloshing signal from the EVAP 
control system pressure sensor

• Harness or connectors

(EVAP control system pressure sensor 
circuit is shorted.)
[Crankshaft position (CKP) sensor (POS) 
circuit is shorted.]
[Accelerator pedal position (APP) sensor 
2 circuit is shorted.]
(Refrigerant pressure sensor circuit is 
shorted.)

• EVAP control system pressure sensor
• CKP sensor (POS)
• APP sensor
• Refrigerant pressure sensor