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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Engine Controls - Self-Diagnostics - Q45) >> Diagnostic Tests >> DTC P1447: EVAP Control System Purge Flow Monitoring >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Infiniti Q45. However, it is still accessible from the selected car via links, so may be relevant.
  1. Inspect EVAP canister for cracks. See Figure. Replace, if cracked. If EVAP canister is not cracked, go to next step.
  2. If using CONSULT-II, go to next step. If using generic scan tool, go to step  4.
  3. Disconnect vacuum hose connected to EVAP-CPVCV at EVAP service port. See Figure. Connect vacuum gauge to disconnected hose. Start engine and let it idle. Select PURG VOL CONT/V in ACTIVE TEST mode with CONSULT-II. Increase engine speed to 2000 RPM. While observing vacuum gauge, press "Qd" and "Qu" on CONSULT-II screen to adjust PURG VOL CONT/V opening. Vacuum should exist when PURG VOL CONT/V opening is 100 percent. Vacuum should not exist when PURG VOL CONT/V opening is zero percent. If operation is as specified, go to step  7. If operation is not as specified, go to step  5.
  4. Start engine and warm to normal operating temperature. Turn ignition off. Disconnect vacuum hose connected to EVAP-CPVCV at EVAP service port. See Figure. Connect vacuum gauge to disconnected hose. Start engine and let it idle for at least 80 seconds. While observing vacuum gauge, increase engine speed to 2000 RPM. Vacuum should exist. Release throttle. Vacuum should not exist. If operation is as specified, go to step  8. If operation is not as specified, go to next step.
  5. Check EVAP purge line for blockage or improper connections. Also, check intake manifold purge port for blockage. If a problem is found, repair as necessary. If no problem is found, go to next step.
  6. If using CONSULT-II, go to next step. If using generic scan tool, go to step  8.
  7. Disconnect hoses from EVAP-CPVCV. See Figure. Command PURG VOL CONT/V to 100 percent with CONSULT-II. Air should flow between EVAP-CPVCV ports "A" and "B". Command PURG VOL CONT/V to zero percent. Air should not flow between EVAP-CPVCV ports "A" and "B". If operation is as specified, go to step  9. If operation is not as specified, go to next step.
  8. Turn ignition off. Remove EVAP-CPVCV. See Figure. Using jumper wires, apply battery voltage to EVAP-CPVCV terminals. See Figure. Air should flow between ports "A" and "B". Remove jumper wires. Air should not flow. If operation is as specified, go to next step. If operation is not as specified, replace EVAP-CPVCV.
  9. Check for disconnection or improper connection of hose connected to EVAP-CSPS. If a problem is found, repair as necessary. If no problem is 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 function. See appropriate DTC CONFIRMATION TEST under DTC P0450: EVAP CONTROL SYSTEM PRESSURE SENSOR. If 1st trip DTC is detected, replace EVAP-CSPS. If 1st trip DTC is not detected, go to next step.
  11. Disconnect hose connected to EVAP-CVCV. Check hose for blockage. If blockage exists, clean hose with compressed air. If blockage does not exist, 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.
  12. If using CONSULT-II, go to next step. If using generic scan tool, go to step  14.
  13. 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  15. If operation is not as specified, clean EVAP-CVCV with compressed air, and retest. If operation is still not as specified, replace EVAP-CVCV.
  14. 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.
  15. Check EVAP purge line for evidence of leaks. If a leak is found, repair as necessary. If no leak is found, clean EVAP purge line with compressed air. Go to next step.
  16. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
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