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Home >> Acura >> 2007 >> RDX >> Repair and Diagnosis >> Engine Mechanical >> Auxiliary Emission Control Systems >> EVAP System >> Fuel Cap Warning Message System Troubleshooting
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Fuel Cap Warning Message System Troubleshooting

Special Tools Required 

  1. Check the fuel fill cap (the cap must say "Tighten to click"). It should turn 1/4 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  13.

  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.
    Fig 1: Identifying Fuel Fill Cap Seal, Fuel Fill Pipe Mating Surface And Fuel Fill Cap Tether Cord
    G05444891Courtesy of AMERICAN HONDA MOTOR CO., INC.

    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  13.

    NO  - Go to step  3.

  3. Reinstall and tighten the fuel fill cap.
  4. Clear the DTC with the HDS.
  5. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle for 1 minute.
  6. Test drive at 45 mph (72 km/h) for 1 minute or more.

    Does the fuel cap warning message come on? 

    YES  - Go to step  7.

    NO  - Intermittent failure, the system is OK at this time.

  7. Turn the ignition switch OFF.
  8. Remove the intake air duct (air flow tube) (see step 19 on page 9-16).
  9. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B) in the engine compartment, and connect a T-fitting (C) from the vacuum gauge and the vacuum pump/gauge 0-30 in.Hg, to the EVAP canister purge valve as shown.
    Fig 2: Connecting T-Fitting From Vacuum Gauge And Vacuum Pump/Gauge To EVAP Canister Purge Valve
    G05444892Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Turn the ignition switch ON (II).
  11. Apply vacuum to the hose about 2 kPa (0.6 in.Hg, 15 mmHg).
  12. Select EVAP PCS ON in the INSPECTION MENU with the HDS.

    Does the vacuum release immediately? 

    YES  - Check for blockage the vacuum hose between EVAP canister purge valve and the EVAP canister, then go to step  13.

    NO  - Replace the EVAP canister purge valve (see EVAP CANISTER PURGE VALVE REPLACEMENT ), then go to step  13.

  13. Install the parts in the reverse order of removal.
  14. Turn the ignition switch ON (II).
  15. Reset the PCM with the HDS.
  16. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  17. Start the engine. Hold the engine speed 3,000 RPM without load (in Park or neutral) until a radiator fan comes on, then let it idle for 1 minute.
  18. Test drive at 45 mph (72 km/h) for 1 minute or more.

    Does the fuel cap warning message come on? 

    YES  - Go to step  1 and recheck.

    NO  - Troubleshooting is complete.