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DTC P1447: EVAP Control System Purge Flow Monitoring: Procedure

  1. Check EVAP canister for cracks and replace as necessary. Start engine and warm to normal operating temperature. Turn ignition off. Disconnect vacuum hose from EVAP Canister Purge Control Valve (EVAP-CPCV). See Figure. Install vacuum gauge with a "T" between vacuum hose and EVAP-CPCV. Start engine and let idle for at least 60 seconds. Observe vacuum gauge while increasing engine speed to 2000 RPM. Vacuum should exist. Release throttle. Vacuum should not exist. If vacuum is as specified, go to step  4. If vacuum is not as specified, go to next step.
  2. Turn ignition off. Disconnect purge hoses from EVAP-CPCV and EVAP Canister Purge Volume Control Valve (EVAP-CPVCV). Ensure air flows through hoses and purge port freely. Ensure vacuum check valve is installed properly. See VACUUM DIAGRAMS article. Clean or repair as necessary. Go to next step.
  3. Attempt to blow air into port on colored side of vacuum check valve. Air should not flow. Blow air into port on other side of vacuum check valve. Air should flow. Replace vacuum check valve if operation is not as specified. If vacuum check valve is okay, check EVAP-CPCS. See DTC P1492: EVAP CANISTER PURGE CONTROL SOLENOID (EVAP-CPCS) . Replace as necessary. If EVAP-CPCS is okay, go to next step.
  4. Check EVAP-CPVCV. See DTC P0443: EVAP CANISTER PURGE VOLUME CONTROL VALVE (EVAP-CPVCV) . Replace, if necessary. If EVAP-CPVCV is okay, check EVAP-CPCV. See DTC P1493: EVAP CANISTER PURGE CONTROL VALVE (EVAP-CPCV) . Replace, if necessary. If EVAP-CPCV is okay, go to next step.
  5. Check EVAP-CSPS. See DTC P0450: EVAP CONTROL SYSTEM PRESSURE SENSOR (EVAP-CSPS) . Replace, if necessary. If EVAP-CSPS is okay, check EVAP-CVCV. See DTC P0446: EVAP CANISTER VENT CONTROL VALVE (EVAP-CVCV) . Replace, if necessary. If EVAP-CVCV is okay, go to next step.
  6. Check EVAP purge line for leaks. Replace, if necessary. If EVAP purge line is okay, clean with compressed air. Test is complete. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
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