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Idle Speed Inspection

NOTE:
  • Before checking the idle speed, check these items:
    • The malfunction indicator lamp (MIL) has not been reported on, and there are no DTCs.
    • Ignition timing
    • Spark plugs
    • Air cleaner
    • PCV system
  • Apply the parking brake (check the headlight OFF).
  1. Disconnect the evaporative emission (EVAP) canister purge valve connector.
  2. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
    Fig 1: Identifying Data Link Connector
    G06264691Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Make sure the HDS communicates with the ECM/ PCM. If it doesn't, go to the DLC circuit troubleshooting (see DLC CIRCUIT TROUBLESHOOTING ).
  4. Start the engine. Hold the engine speed at 3,000 RPM (min-1 ) without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  5. Check the idle speed without load conditions: headlights, blower fan, radiator fan, and air conditioner off.

    Idle speed should be: 

    K20Z2 engine: 

    ENGINE SPEED REFERENCE

    M/T 700±50 RPM (min-1 )
    A/T 800±50 RPM (min-1 ) (in Park or neutral)

    K20Z3 engine: 

    ENGINE SPEED REFERENCE

    M/T 750±50 RPM (min-1 )
  6. Let the engine idle for 1 minute with high electric load (A/C switch on, temperature set to max cool, blower fan on High, and headlights on high beam).

    Idle speed should be: 

    K20Z2 engine: 

    ENGINE SPEED REFERENCE

    M/T 780±50 RPM (min-1 )
    A/T 800±50 RPM (min-1 ) (in Park or neutral)

    K20Z3 engine: 

    ENGINE SPEED REFERENCE

    M/T 750±50 RPM (min-1 )
    NOTE: If the idle speed is not within specification, do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE  ). If the idle speed is still not within specification, go to symptom troubleshooting.
  7. Reconnect the EVAP canister purge valve connector.