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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 (on EVAP service port side) from EVAP Canister Purge Volume Control Valve (EVAP-CPVCV). Install vacuum gauge to port on EVAP-CPVCV. Go to next step.
  2. Start engine and let idle for at least 80 seconds. Increase engine speed to 2000 RPM and observe vacuum gauge. 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.
  3. Turn ignition off. Disconnect purge hoses from EVAP-CPVCV. Ensure air flows through hoses and purge port freely. If hoses and port are okay, repair EVAP-CPVCV or circuit. See DTC P0443: EVAP CANISTER PURGE VOLUME CONTROL VALVE (EVAP-CPVCV) .
  4. 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.
  5. Check EVAP purge line for leaks. Replace, if necessary. If EVAP purge line is okay, clean purge line with compressed air. Test is complete. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.