LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Honda >> 2003 >> S2000 >> Repair and Diagnosis >> Engine Performance >> System >> EVAP System >> DTC Troubleshooting >> DTC P1457: EVAP Control System Leakage (EVAP Canister System) >> Canister System Leak Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Canister System Leak Test

  1. 27. Turn the ignition switch OFF.
  2. 28. Connect two three-way T-fittings (A) into the hose from the EVAP canister to the EVAP two way valve. Connect the FTP sensor to one of the T-fittings and a commercially available vacuum pump/gauge, 0-30 in.Hg, to the other.
    Fig 1: Connecting Two Three-Way T-Fittings
    G03692865Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. 29. Remove the vent hose from the EVAP canister vent shut valve (A), and cap the port (B) to seal the fresh air vent for the EVAP canister.
    Fig 2: Removing Vent Hose From EVAP Canister Vent Shut Valve
    G03692866Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. 30. Turn the ignition switch ON (II).
  5. 31. While monitoring FTP sensor voltage with the HDS, or measuring voltage between ECM connector terminals A29 and C18, slowly pump the vacuum pump.
  6. 32. Continue to pump vacuum until the voltage drops to about 1.5 V. Make sure that the engine coolant temperature is still above 95 °F (35 °C) and your vacuum pump has no leak.
  7. 33. Check the voltage for 20 seconds.

    Does the voltage drop to 1.5 V and hold for at least 20 seconds? 

    1. YES -  Inspect the EVAP canister vent shut valve line and connections.
    2. NO -  Go to step 34.
  8. 34. Turn the ignition switch OFF.
  9. 35. Disconnect the quick-connect fitting (A) from the EVAP canister, and plug the canister port (B).
    Fig 3: Disconnecting Quick-Connect Fitting From EVAP Canister
    G03692867Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. 36. Turn the ignition switch ON (II).
  11. 37. While monitoring FTP sensor voltage with the HDS, or measuring voltage between ECM connector terminals A29 and C18, slowly pump the vacuum pump.
    Fig 4: Measuring Voltage Between ECM Connector Terminals A29 And C18
    G03692868Courtesy of AMERICAN HONDA MOTOR CO., INC.
  12. 38. Continue to pump vacuum until the voltage drops to about 1.5 V. Make sure the engine coolant temperature is still above 95 °F (35 °C) and your vacuum pump/gauge has no leak.
  13. 39. Monitor the voltage continuously for 20 seconds.

    Does the voltage drop to 1.5 V and hold for at least 20 seconds? 

    1. YES -  Inspect the fuel tank vapor control line and connections.
    2. NO -  Go to step 40.
  14. 40. Turn the ignition switch OFF.
  15. 41. Disconnect the purge line hose (A) from the canister at the metal line, and plug the hose (B).
    Fig 5: Disconnecting Purge Line Hose From Canister At Metal Line, And Plug Hose
    G03692869Courtesy of AMERICAN HONDA MOTOR CO., INC.
  16. 42. Turn the ignition switch ON (II).
  17. 43. While monitoring FTP sensor voltage with the HDS, or measuring voltage between ECM connector terminals A29 and C18, slowly pump the vacuum pump/gauge.
  18. 44. Continue to pump vacuum until the voltage drops to about 1.5 V. Make sure that the engine coolant temperature is still above 95 °F (35 °C) and your vacuum pump/gauge has no leak.
  19. 45. Check the voltage for 20 seconds.

    Does the voltage drop to 1.5 V and hold at least 20 seconds? 

    1. YES -  Inspect the EVAP canister purge valve line and connections. If they are OK, test the EVAP two way valve (see EVAP TWO WAY VALVE TEST  ), and the fuel tank vapor control valve (see FUEL TANK VAPOR CONTROL VALVE TEST  ).
    2. NO -  Replace the EVAP canister.
scientia non olet · About LEMON Manuals