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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Nissan Xterra and 2002 Nissan Frontier. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition off. Disconnect hose from EVAP-CVCV. See Figure . Check hose for blockage. If blockage exists, clean hose with compressed air. If blockage does not exist, go to next step.
  2. Remove EVAP-CVCV. Check for rust in port "B". See Figure . If rust exists, replace EVAP-CVCV. If rust does not exist, go to next step.
  3. If using CONSULT-II, go to next step. If using generic scan tool, go to step  5 .
  4. Reconnect all harness connectors. Turn ignition on. Perform VENT CONTROL/V in ACTIVE TEST mode with CONSULT-II. When VENT CONTROL/V is ON, air should not flow between ports "A" and "B". When VENT CONTROL/V is OFF, air should flow between ports "A" and "B". It should take less than one second for valve to open or close. If operation is as specified, go to step  6 . If operation is not as specified, clean EVAP-CVCV with compressed air, and retest. If operation is still not as specified, replace EVAP-CVCV.
  5. Using jumper wires, apply battery voltage to EVAP-CVCV terminals. See Figure . Air should not flow between ports "A" and "B". Remove jumper wires. Air should flow. EVAP-CVCV should switch in less than one second. If operation is as specified, go to next step. If operation is not as specified, clean EVAP-CVCV with compressed air, and retest. If operation is still not as specified, replace EVAP-CVCV.
  6. Remove vacuum cut valve. See Figure . Plug ports "C" and "D". See Fig 1 . Using a hand vacuum pump, apply vacuum to port "A". Vacuum should not exist at port "B". Apply vacuum to port "B". Vacuum should exist at port "A". Blow air into port "B". Air should flow out of port "A" with some resistance. Unplug ports "C" and "D". Blow air into port "A". Air should flow freely out of port "C". Blow air into port "B". Air should flow freely out of port "D". If operation is as specified, go to next step. If operation is not as specified, replace vacuum cut valve.
  7. Remove EVAP canister with EVAP-CVCV attached. Invert EVAP canister and attempt to drain water from EVAP canister. If water drains from EVAP canister, go to next step. If water does not drain from EVAP canister, go to step  9 .
  8. Weigh EVAP canister with EVAP-CVCV attached. If EVAP canister weighs less than 4.0 lbs. (1.8 kg), go to next step. If EVAP canister weighs 4.0 lbs. (1.8 kg) or more, inspect EVAP canister for damage and hoses to water separator for poor connections or blockage. Repair as necessary.
  9. Check for disconnection or improper connection of hose connected to EVAP-CSPS. If problem is found, repair as necessary. If problem is not found, disconnect EVAP-CSPS harness connector. If water exists in connector, replace EVAP-CSPS. If water does not exist in connector, go to next step.
  10. Check EVAP-CSPS and circuit by performing appropriate DTC CONFIRMATION TEST under DTC P0452 OR DTC P0453: EVAP CONTROL SYSTEM PRESSURE SENSOR. If problem is found, repair as necessary. If problem is not found, go to next step.
  11. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
Fig 1: Identifying Vacuum Cut Valve Ports
G99B54834Courtesy of NISSAN MOTOR CO., U.S.A.
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