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DTC P0441: EVAP Control System Insufficient Purge Flow

NOTE: PCM detects insufficient EVAP control system purge flow by monitoring purge line vacuum with EVAP purge flow switch. This DTC does not apply to all vehicles, refer to vehicle underhood EMISSION GROUP IDENTIFICATION label for confirmation.
  1. Perform PCM reset procedure. See PCM RESET PROCEDURE/CLEARING DTCS  . Connect SCS service connector. Test drive vehicle with A/C off and transmission in D4 position (A/T) or 5th gear (M/T), until readiness code comes on. Test drive vehicle for approximately 10 minutes, including gradual acceleration from 50 MPH. If DTC P0441 is indicated, go to next step. If DTC P0441 is not indicated, problem is intermittent, system is okay at this time. Check for poor connections or loose wires between EVAP purge control solenoid valve, control box (EVAP purge flow switch) and PCM connectors. See the WIRING DIAGRAMS article.
  2. Check EVAP system vacuum hoses for proper routing, leaks or restrictions. See the VACUUM DIAGRAMS article. Repair vacuum hoses as necessary. If hoses are okay, disconnect EVAP control canister vacuum hose from vacuum port on top of throttle body. Using a vacuum gauge, check for vacuum at vacuum port. With engine warm and at idle, vacuum should not be present. If vacuum is present, check throttle cable for binding or sticking and proper adjustment. Vacuum should be present with throttle slightly opened from idle. If vacuum is not present, check throttle body port for restrictions. Clean or replace throttle body as necessary. If throttle body is okay, go to next step.
  3. Disconnect vacuum hose from EVAP purge flow switch and connect a vacuum gauge to hose. Install jumper wire between PCM connector "A" terminal A10 and terminal A15. See Figure . Start engine. Increase and hold engine speed at 1500-3000 RPM. If there is less than 2.0 in. Hg vacuum, go to step 6). If there is 2.0 in. Hg vacuum or more, go to next step.
  4. Turn ignition off. Reconnect hose to EVAP purge flow switch. Start engine. Increase and hold engine speed to 1500-3000 RPM. Measure voltage between PCM connector terminal C20 and terminal A10. See Figure . If more than one volt exists, go to next step. If one volt or less exists, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.
  5. Turn ignition off. Disconnect 2-pin EVAP purge flow switch connector. Install jumper wire between EVAP purge flow switch connector terminal No. 1 (Brown wire) and terminal No. 2 (Black wire). Turn ignition on. Measure voltage between PCM connector terminal C20 and terminal A10. See Figure . If more than one volt exists, repair open in wire between PCM and purge flow switch. If one volt or less exists, replace EVAP purge flow switch. See the WIRING DIAGRAMS article.
  6. Turn ignition off. Disconnect EVAP purge control solenoid valve 2-pin connector. Turn ignition on. Measure voltage between ground and EVAP purge control solenoid connector terminal No. 2 (Yellow/Black wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short in Yellow/Black wire between EVAP purge control solenoid valve and PGM-FI main relay. See the WIRING DIAGRAMS article.
  7. Turn ignition off. Install a jumper wire between EVAP purge control solenoid valve harness connector terminals. Turn ignition on. Measure voltage between PCM connector terminal A10 and terminal A15. See Figure . If battery voltage exists, replace EVAP purge control solenoid valve. If battery voltage does not exist, repair open in Red/Yellow wire between PCM connector terminal A15 and EVAP purge control solenoid valve. See the WIRING DIAGRAMS article.
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