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Home >> Hyundai >> 2004 >> Tiburon Base, Standard >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Fuel System (2.0L) >> DTC Troubleshooting Procedures >> DTC P1166: O2 Sensor System Lambda Bank Controller At The Limit (Bank 1) >> Inspection Procedures
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Inspection Procedures

  1. CHECK DTC RELATING TO HO2S, FUEL SYSTEM, EVAP SYSTEM, OR IGNITION SYSTEM
    1. Connect a HI-Scan (Pro) to the data link connector.
    2. Turn ignition switch to ON position and monitor any other DTCs.

    Are DTCs relating to HO2S, fuel system, EVAP system, or ignition system set? 

    No: Go to next

    Yes: Do all repairs associated with those codes before proceeding with this procedure.

  2. CHECK AIR LEAKAGE AND CONNECTIONS
    1. Check for air leakage and bad connections. (especially PCV, PCSV, ISCA hose, throttle body, intake manifold, and brake booster).

    Are all connections okay? 

    Yes: Go to next step.

    No: Repair or replace it.

  3. CHECK PCSV
    1. Disconnect the PCSV connector and the EVAP hose (PCSV side) between the PCSV and the canister.
    2. Check vacuum at the PCSV.

    Is PCSV normal? 

    Yes: Go to next

    No: Replace it.

  4. CHECK FUEL LINE PRESSURE
    1. Start the engine with the fuel pump disconnected and wait until it stops by itself to release fuel pressure.
    2. Attach a fuel pressure gauge to the fuel delivery pipe.
    3. Start the engine and check the fuel pressure at idle.

    Is fuel line pressure within specification? 

    Yes: Go to next

    No: Check fuel delivery system.

  5. CHECK INJECTOR FOR NORMAL OPERATION
    1. Start the engine and check the engine RPM decrease when disconnecting each injector connector in sequence.
    2. Measure the decreasing engine RPM of all cylinders.

    Is there any cylinder with no change in RPM or only a small RPM change? 

    No: Go to next

    Yes: Repair or replace it.

  6. CHECK SPARK PLUGS FOR NORMAL OPERATION
    1. Remove the spark plugs and inspect the spark plug tips.
    2. Check for abnormal color of the spark plug tips compared to other cylinders.

    Is there any spark plug with abnormal color compared to other cylinders? 

    No: Go to next

    Yes: Check engine for mechanical failure. If it is okay, replace spark plugs.

  7. CHECK FRONT HO2S
    1. Temporarily install a good HO2S and check for proper operation.

    Is problem corrected? 

    No: Go to next

    Yes: Replace it.

  8. CHECK ECM INPUT SIGNALS RELATING TO MAFS, TPS, AND ECTS
    1. Check for ECM input signals from the MAFS, TPS, and ECTS.

    Are input signals normal? 

    Yes: Proceed with ECM PROBLEM PROCEDURE  .

    No: Replace all failed parts.

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