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Home >> Honda >> 2009 >> Element SC, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> EVAP System >> DTC Troubleshooting >> DTC P0455, P0456: EVAP System Large Leak Detected; EVAP System Very Small Leak Detected >> Special Tools Required
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Special Tools Required

Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available

NOTE:
  • Before you troubleshoot, record all freeze data and any on-board snapshot, and review GENERAL TROUBLESHOOTING INFORMATION .
  • Fresh fuel has a higher volatility that will create greater pressure/vacuum. The optimum condition for testing is less than a full tank of fresh fuel. If possible, to assist in leak detection, add 1 gallon of fresh fuel to the tank (as long as it will not fill the tank) just before starting these procedures.
  1. Check the fuel fill cap (the cap must say "TIGHTEN TO CLICK"). It should turn 1/4 turn after it's tight, then it clicks.

    Is the correct fuel fill cap installed and properly tightened? 

    YES  - Go to step  2.

    NO  - Replace or tighten the cap, then go to step 29.

  2. Check the fuel fill cap seal (A) and the fuel fill pipe mating surface (B). Verify that the fuel fill cap tether cord (C) is not caught under the cap.

    Is the fuel fill cap seal missing or damaged, is the fuel fill pipe damaged, or is the tether cord caught under the cap? 

    YES  - Replace the fuel fill cap or the fuel fill pipe, then go to step.

    NO  - Go to step  3.

    Fig 1: Identifying Fuel Fill Cap Seal, Fuel Fill Pipe Mating Surface & Fuel Fill Cap Tether Cord
    G05449306Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Turn the ignition switch to ON (II).
  4. Clear the DTC with the HDS.
  5. Do the EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.

    Is the result OK? 

    YES  - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the FTP sensor, the EVAP canister purge valve, or the EVAP canister vent shut valve and the ECM/PCM.

    NO  - Go to step  6.

  6. Turn the ignition switch to LOCK (0).
  7. Check for a poor connection or damage at the fuel tank vapor recirculation tube.

    Is the tube OK? 

    YES  - Go to step  8.

    NO  -

    • Replace the fuel tank vapor recirculation tube, then go to step  29.
    • If necessary, replace the fuel tank (see FUEL TANK REPLACEMENT ), then go to step  29.
  8. Disconnect the fuel tank vapor recirculation tube (A) and the fresh air hoses (B) from the EVAP canister (C), and plug the EVAP canister ports (D).
    Fig 2: Identifying Fuel Tank Vapor Recirculation Tube, Fresh Air Hoses, EVAP Canister & EVAP Canister Ports
    G00486290Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Disconnect the vacuum hose (purge line) (A) from the EVAP canister purge valve in the engine compartment, and the vacuum pump/gauge, 0-30 in.Hg, to the hose as shown below.
    Fig 3: Identifying EVAP Canister Purge Valve & Vacuum Hose (Engine Side)
    G00487500Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Turn the ignition switch to ON (II).
  11. Select EVAP CVS ON in the INSPECTION MENU with the HDS.
  12. Apply vacuum to the hose until the FTP reads 1.90 V (-0.59 in.Hg, -15.1 mmHg).
    NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
  13. Select EVAP CVS OFF in the INSPECTION MENU with the HDS.
  14. Monitor the FTP SENSOR in the DATA LIST for 1 minute with the HDS.

    Does the voltage increase more than 0.2 V (0.1 in.Hg, 2.5 mmHg)? 

    YES  - Go to step  15.

    NO  - Go to step  22.

  15. Turn the ignition switch to LOCK (0).
  16. Disconnect the vacuum pump/gauge from the EVAP canister purge valve.
  17. Reconnect the vacuum hose (canister side) to the EVAP canister purge valve (A), disconnect the vacuum hose (engine side) (B) from the EVAP canister purge valve, and connect a vacuum pump/gauge valve to the EVAP canister purge valve as shown below.
    Fig 4: View Of EVAP Canister Purge Valve & Vacuum Hose (Engine Side)
    G00487501Courtesy of AMERICAN HONDA MOTOR CO., INC.
  18. Turn the ignition switch to ON (II).
  19. Apply vacuum to the hose until the FTP reads 1.90 V (-0.59 in.Hg, -15.1 mmHg).
    NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
  20. Monitor the FTP SENSOR in the DATA LIST for 1 minute with the HDS.

    Does the voltage increase more than 0.2 V (0.1 in.Hg, 2.5 mmHg)? 

    YES  - Go to step  21

    NO  - Replace the EVAP canister purge valve (see

  21. Check for a loose or damaged EVAP canister purge line between the EVAP canister and the EVAP canister purge valve, or check for a leaking EVAP canister.

    Are the line and the EVAP canister OK? 

    YES  - Replace these parts, then go to step  29:

    • FTP sensor O-ring
    • EVAP canister vent shut valve case and O-ring
    • EVAP canister

    NO  - Replace the EVAP canister purge line, the EVAP canister purge valve, and/or the EVAP canister, then go to step  29.

  22. Reconnect the fresh air hoses (A) to the EVAP canister (B).
    Fig 5: Identifying Fresh Air Hoses & EVAP Canister
    G00487502Courtesy of AMERICAN HONDA MOTOR CO., INC.
  23. Reconnect the vacuum hose (engine side) to the EVAP canister purge valve (A) and disconnect the vacuum hose (EVAP canister side) (B) from the EVAP canister purge valve, then connect a vacuum pump/gauge, 0-30 in.Hg, to the vacuum hose as shown below.
    Fig 6: Identifying EVAP Canister Purge Valve & Vacuum Hose (EVAP Canister Side)
    G00487503Courtesy of AMERICAN HONDA MOTOR CO., INC.
  24. Select EVAP CVS ON in the INSPECTION MENU with the HDS.
  25. Apply vacuum to the hose until the FTP reads 1.90 V (-0.59 in.Hg, -15.1 mmHg).
    NOTE: Be careful not to exceed the vacuum. If you do, the FTP sensor can be damaged.
  26. Monitor the FTP SENSOR in the DATA LIST for 1 minute with the HDS.

    Does the voltage increase more than 0.2 V (0.1 in.Hg, 2.5 mmHg)? 

    YES  - Replace the EVAP canister vent shut valve (see EVAP CANISTER VENT SHUT VALVE REPLACEMENT  ), then go to step  29.

    NO  - Go to step  26.

  27. Select EVAP CVS OFF in the INSPECTION MENU with the HDS.
  28. Check these parts for looseness or damage:
    • Fuel fill pipe
    • Fuel vapor return pipe

    Are the parts OK? 

    YES  - Check the fuel pump base gasket (see FUEL TANK UNIT REMOVAL/INSTALLATION ), and check the fuel tank, then go to step  29.

    NO  - Repair or replace the damaged parts, then go to step  29.

  29. Reconnect all hoses and connectors.
  30. Turn the ignition switch to ON (II).
  31. Reset the ECM/PCM with the HDS.
  32. Do ECM/PCM IDLE LEARN PROCEDURE .
  33. Do the EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.

    Is the result OK? 

    YES  - Go to step  34.

    NO  - Check for poor connections or loose terminals at the FTP sensor, the EVAP canister purge valve, or the EVAP canister vent shut valve and the ECM/PCM, then go to step  1.

  34. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P0455 and/or P0456 indicated? 

    YES  - Check for poor connections or loose terminals at the FTP sensor, the EVAP canister purge valve, the EVAP canister vent shut valve, and the ECM/PCM, then go to step  1

    NO  - Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.