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Home >> Infiniti >> 2001 >> I30 Base, RE4F04B >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1447: EVAP Control System Purge Flow Monitoring >> Procedure
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DTC P1447: EVAP Control System Purge Flow Monitoring: Procedure

  1. Check EVAP canister for cracks. Replace, if cracked and retest system. If EVAP canister is okay, start engine and warm to normal operating temperature. Turn ignition off. Disconnect EVAP Canister Purge Volume Control Valve (EVAP-CPVCV) hose from EVAP service port. See VACUUM DIAGRAMS article. Start engine and let idle for at least 80 seconds. While quickly increasing engine speed to 2000 RPM, check for vacuum at EVAP-CPVCV hose. Vacuum should exist. If vacuum does not exist, go to next step. If vacuum exists, go to step  3.
  2. Turn ignition off. Check EVAP purge line for leaks or improper connection. Repair as necessary and retest system. If purge line is okay, check hoses between EVAP-CPVCV and purge port for blockage. Also check purge port for blockage. Repair as necessary and retest system. If hoses and purge port are okay, go to next step.
  3. Remove EVAP-CPVCV. Using jumper wires, apply battery voltage between EVAP-CPVCV terminals. See Figure. Check for airflow between ports "A" and "B". Air should flow. 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 and retest system.
  4. Check EVAP-CSPS hose for leak or improper connection. See Figure. Repair as necessary and retest system. If hose is okay, disconnect EVAP-CSPS harness connector. Inspect connector for water. If water does not exist, go to next step. If water exists, replace EVAP-CSPS and retest system.
    5. CAUTION: DO NOT use ECM ground terminals when measuring voltage.
  5. Reconnect all hoses. Start engine and warm to normal operating temperature. Measure voltage between ground and ECM terminal No. 92 (fuel tank temperature sensor signal) by backprobing. See Figure and Figure . Ensure voltage is less than 4.2 volts. Turn ignition off and wait at least 10 seconds. Start engine and wait at least 20 seconds. Select MODE 7 with scan tool. If first trip DTC P0450 is present, replace EVAP-CSPS and retest system. If first trip DTC P0450 is not present, go to next step.
  6. Check for blockage in hose connected to EVAP-CVCV. See Figure. Clean with compressed air, if necessary and retest system. If hose is okay, remove EVAP-CVCV from EVAP canister. Check for rust in port "B". See Figure. If rust exists, replace EVAP-CVCV and retest system. If rust does not exist, go to next step.
  7. Using jumper wires, apply battery voltage between EVAP-CVCV terminals. Air should flow between ports "A" and "B". See Figure. Disconnect jumper wires. Air should not flow between ports "A" and "B". EVAP-CVCV should switch in one second or less. If EVAP-CVCV operates as specified, go to step  9. If EVAP-CVCV does not operate as specified, go to next step.
  8. Clean EVAP-CVCV ports with compressed air and repeat step  7. If EVAP-CVCV is okay, go to next step. If EVAP-CVCV still does not operate as specified, replace EVAP-CVCV and retest system.
  9. Install all removed parts. Start engine and warm to normal operating temperature. Turn ignition off. Disconnect TP switch harness connector. Check continuity between TP switch terminals No. 4 and 5. See Figure. With throttle fully closed, continuity should exist. With throttle partially open or fully open, continuity should not exist. If continuity is as specified, go to step  11. If continuity is not as specified, go to next step.
  10. Adjust TP switch. See ON-VEHICLE ADJUSTMENTS article. Repeat step  9. If continuity is still not as specified, replace TP switch and retest system. If continuity is as specified, go to next step.
  11. Inspect EVAP purge line for leaks. See VACUUM DIAGRAMS article. Repair as necessary and retest system. If no leaks are found, clean EVAP purge line with compressed air and go to next step.
  12. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
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