DTC Confirmation Test

WARNING: This page is about a different car, the 2002 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: If DTC confirmation test has been previously performed, always turn ignition off and wait at least 10 seconds before performing next DTC confirmation test.

NOTE: For best results, perform test when ambient temperature is more than 32°F (0°C).

With CONSULT-II

Turn ignition on. Start engine and warm to normal operating temperature.
Turn ignition off and wait at least 10 seconds. Start engine and let it idle for at least 70 seconds.
Select VC CUT/V BP/V P1491 of EVAPORATIVE SYSTEM in DTC WORK SUPPORT mode with CONSULT-II.
Press START on CONSULT-II screen. When the following conditions are met, TESTING will be displayed on CONSULT-II screen.
- ENG SPEED: 1000-3800 RPM.
- Vehicle speed: 22-75 MPH.
- B/FUEL SCHDL: 1.0-8.2 msec.
Maintain conditions continuously until TESTING changes to COMPLETED (it will take at least 30 seconds). If TESTING is not displayed after 5 minutes, retry from step 2 .
Press SELF-DIAG RESULTS. If NG is displayed, go to DIAGNOSTIC PROCEDURE . If OK is displayed, system is okay at this time.

NOTE: Use the following test to check overall function of vacuum cut valve by-pass valve. During this test, 1st trip DTC may not be confirmed.

With Generic Scan Tool (Overall Function Check)

Remove vacuum cut valve and vacuum cut valve by-pass valve as an assembly. See Figure . Apply vacuum to port "A". See Figure . Vacuum should not exist at port "B". Apply vacuum to port "B". Vacuum should exist at port "A".
Blow air in port "B". Air should flow out of port "A" with some resistance. Using jumper wires, apply battery voltage to by-pass valve terminals. Air should flow freely through ports "A" and "B" in both directions.
If operation is as specified, system is okay at this time. If operation is not as specified, go to DIAGNOSTIC PROCEDURE .