Nissan Maxima Service and Repair Manual: P0442 evap control system

DTC Logic

DTC DETECTION LOGIC

This diagnosis detects leakage in the EVAP purge line using engine intake manifold vacuum.

If pressure does not increase, the ECM will check for leakage in the line between the fuel tank and EVAP canister purge volume control solenoid valve, under the following "Vacuum test" conditions.

The EVAP canister vent control valve is closed to shut the EVAP purge line off. The EVAP canister purge volume control solenoid valve will then be opened to depressurize the EVAP purge line using intake manifold vacuum. After this occurs, the EVAP canister purge volume control solenoid valve will be closed.

CAUTION:

•  Use only a genuine NISSAN fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may illuminate.
•  If the fuel filler cap is not tightened properly, the MIL may illuminate.
•  Use only a genuine NISSAN rubber tube as a replacement.

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following 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.

TESTING CONDITION:

•  Perform "DTC WORK SUPPORT" when the fuel level is between 1/4 and 3/4 full, and vehicle is placed on flat level surface.
•  Always perform test at a temperature of 0 to 30C (32 to 86F).

NOTE: Check that EVAP hoses are connected to EVAP canister purge volume control solenoid valve properly.

2.PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT

1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select "DATA MONITOR" mode with CONSULT.
4. Check that the following conditions are met.

   COOLAN TEMP/S: 0 - 70C (32 - 158F) INT/A TEMP SE: 0 - 30C (32 - 86F)

5. Select "EVP V/S LEAK P0456/P1456" of "EVAPORATIVE SYSTEM" in "DTC WORK SUPPORT" mode with CONSULT.

   Follow the instructions displayed.

NOTE: If the engine speed cannot be maintained within the range displayed on the CONSULT screen

3.PERFORM COMPONENT FUNCTION CHECK

With GST

NOTE: Be sure to read the explanation of EC-26, "SRT Set Driving Pattern" before driving vehicle.

1. Start engine.
2. Drive vehicle according to EC-26, "SRT Set Driving Pattern".
3. Stop vehicle.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON.
6. Turn ignition switch OFF and wait at least 10 seconds.
7. Turn ignition switch ON.
8. Check 1st trip DTC.

Diagnosis Procedure

1.CHECK FUEL FILLER CAP DESIGN

1. Turn ignition switch OFF
2. Check for genuine NISSAN fuel filler cap design.

2.CHECK FUEL FILLER CAP INSTALLATION

Check that the cap is tightened properly by rotating the cap clockwise.

3.CHECK FUEL FILLER CAP FUNCTION

Check for air releasing sound while opening the fuel filler cap.

4.CHECK FUEL TANK VACUUM RELIEF VALVE

5.CHECK FOR EVAP LEAKAGE

6.CHECK DRAIN FILTER

7.CHECK EVAP CANISTER VENT CONTROL VALVE

Check the following.

• EVAP canister vent control valve is installed properly.

  Refer to FL-16, "Removal and Installation".

• EVAP canister vent control valve.

8.CHECK IF EVAP CANISTER IS SATURATED WITH WATER

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

9.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).

10.DETECT MALFUNCTIONING PART

Check the following.

• EVAP canister for damage
• EVAP hose between EVAP canister and drain filter for clogging or poor connection

11.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

With CONSULT

1. Disconnect vacuum hose from EVAP canister purge volume control solenoid valve at EVAP service port.
2. Start engine.
3. Perform "PURG VOL CONT/V" in "ACTIVE TEST" mode.
4. Touch "Qu" on CONSULT screen to increase "PURG VOL CONT/V" opening to 100%.
5. Check vacuum hose for vacuum.

Vacuum should exist.

12.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION

Without CONSULT

1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose from EVAP canister purge volume control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.

Vacuum should exist.

13.CHECK VACUUM HOSE

Check vacuum hoses for clogging or disconnection.

14.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE

15.CHECK FUEL TANK TEMPERATURE SENSOR

16.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

17.CHECK EVAP PURGE LINE

Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks or improper connection.

18.CLEAN EVAP PURGE LINE

Clean EVAP purge line (pipe and rubber tube) using air blower.

19.CHECK EVAP/ORVR LINE

Check EVAP/ORVR line between EVAP canister and fuel tank for clogging, kinks, looseness and improper connection.

20.CHECK RECIRCULATION LINE

Check recirculation line between filler neck tube and fuel tank for clogging, kinks, cracks, looseness and improper connection.

21.CHECK REFUELING EVAP VAPOR CUT VALVE

22.CHECK FUEL LEVEL SENSOR

23.CHECK INTERMITTENT INCIDENT

Component Inspection

FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)

1.CHECK FUEL FILLER CAP

1. Turn ignition switch OFF.
2. Remove fuel filler cap. Refer to FL-10, "Exploded View".
3. Wipe clean valve housing.
4. Install fuel filler cap adapter (commercial service tool) to fuel filler cap.
5. Check valve opening pressure and vacuum.

Pressure: 15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 - 2.90 psi)
Vacuum: −6.0 to −3.3 kPa (−0.061 to −0.034 kg/cm2, −0.87 to −0.48 psi)

2.REPLACE FUEL FILLER CAP

Replace fuel filler cap. Refer to FL-10, "Exploded View".

CAUTION: Use only a genuine fuel filler cap as a replacement. If an incorrect fuel filler cap is used, the MIL may illuminate.

DRAIN FILTER

1. Check visually for insect nests in the drain filter air inlet.
2. Check visually for cracks or flaws in the appearance.
3. Check visually for cracks or flaws in the hose.
4. Blow air into port A and check that it flows freely out of port B.
5. Block port B.
6. Blow air into port A and check that there is no leakage.
7. If NG, replace drain filter.