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.

Fig 1: EVAP Control System - System Diagram

Courtesy of NISSAN MOTOR CO., U.S.A.

DTC DETECTION CONDITION CHART

DTC No.	Trouble diagnosis name	DTC detecting condition	Possible cause
P0442	EVAP control system small leakage detected (negative pressure)	EVAP control system has a leakage, EVAP control system does not operate properly.	Incorrect fuel tank vacuum relief valve Incorrect fuel filler cap used Fuel filler cap remains open or does not close. Foreign matter caught in fuel filler cap. Leakage is in line between intake manifold and EVAP canister purge volume control solenoid valve. Foreign matter caught in EVAP canister vent control valve. EVAP canister or fuel tank leakage EVAP purge line (pipe and rubber tube) leakage EVAP purge line rubber tube bent Loose or disconnected rubber tube EVAP canister vent control valve and the circuit EVAP canister purge volume control solenoid valve and the circuit Fuel tank temperature sensor O-ring of EVAP canister vent control valve is missing or damaged EVAP canister is saturated with water EVAP control system pressure sensor Fuel level sensor and the circuit Refueling EVAP vapor cut valve ORVR system leakage

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.