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Home >> Infiniti >> 2001 >> G20 Base, Standard, RS5F70W >> 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. Inspect EVAP canister for cracks. Replace, if necessary and retest system. If EVAP canister is not cracked, go to next step.
  2. Start engine and warm to normal operating temperature. Turn ignition off. Disconnect EVAP-CPVCV hose from EVAP service port. See Figure and Figure . Start engine and let it 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  4.
  3. Check EVAP purge hose for blockage or improper connections. Also check intake manifold purge port for blockage. Repair as necessary and retest system. If no problems are found, go to next step.
  4. Turn ignition off. Remove EVAP-CPVCV. 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 and retest system.
  5. Check EVAP-CSPS hose for leak. See Figure. Repair as necessary and retest system. If hose is okay, disconnect EVAP-CSPS harness connector. If water exists in connector, replace EVAP-CSPS and retest system. If connector is okay, go to next step.
    6. CAUTION: DO NOT apply more than 5.91 in. Hg (20 kPa) of vacuum to EVAP-CSPS. Replace EVAP-CSPS if it has been dropped from a height of more than 20" (.5 m) onto a hard surface such as concrete.
    CAUTION: DO NOT use ECM ground terminals when measuring voltage.
  6. Remove EVAP-CSPS with its harness connector connected. See Figure. Turn ignition on. Using a hand vacuum pump, apply 2.76 in. Hg (9.3 kPa) of vacuum to EVAP-CSPS. Measure voltage between ground and ECM terminal No. 84 by backprobing. See Figure and Figure . Voltage should be .4-.6 volt. Disconnect vacuum pump. Voltage should be 3.0-3.6 volts. If voltage is as specified, go to next step. If voltage is not as specified, replace EVAP-CSPS and retest system.
  7. Disconnect EVAP-CVCV hose. See Figure. Check hose for blockage. Repair as necessary and retest system. If hose is okay, remove EVAP-CVCV. 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.
  8. 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 step  10. If operation is not as specified, go to next step.
  9. Clean EVAP-CVCV ports with compressed air. Repeat step  8. If EVAP-CVCV still does not operate as specified, replace EVAP-CVCV and retest system. If EVAP-CVCV is okay, go to next step.
  10. Install all removed parts. Start engine and warm to normal operating temperature. Turn ignition off. Disconnect vacuum hose from throttle opener. See Figure. Using a hand vacuum pump, apply vacuum to throttle opener until throttle opener rod does not contact throttle drum. Disconnect closed Throttle Position (TP) switch harness connector. Check continuity between closed TP switch terminals No. 4 and 5. See Figure. Continuity should exist when throttle is closed. Continuity should not exist when throttle is open. If continuity is as specified, go to step  12. If continuity is not as specified, go to next step.
  11. Adjust throttle position switch. See ON-VEHICLE ADJUSTMENTS article. If adjustment is not possible, replace throttle position switch and retest system. If adjustment is possible, go to next step.
  12. Check EVAP purge line for evidence of leaks. Repair as necessary and retest system. If no leaks are found, clean EVAP purge line with compressed air. Go to next step.
  13. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
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