2004 Hyundai Tiburon Base, StandardFACTORY OEM SERVICE PROCEDURE

Inspection Procedures

  1. PROBLEM VERIFICATION
    1. Connect Hi-Scan (Pro) to data link connector and warm up engine to normal operating temperature.
    2. Using Hi-Scan (Pro), monitor HO2S signal.

    Does the HO2S signal switch from lean to rich or from rich to lean? 

    No: Go to next

    Yes: Problem is intermittent or was repaired and engine control module memory was not cleared. Proceed with INTERMITTENT PROBLEM PROCEDURE  .

  2. CHECK HO2S AND ECM CONNECTORS
    1. Thoroughly check connectors for loose, poor connection, bent, corrosion, contamination, deterioration, or damage.

    Are all connectors good? 

    Yes: Go to next

    No: Repair or replace it.

  3. CHECK FOR OPEN IN HARNESS
    1. Turn ignition switch to OFF and disconnect ECM connector.
    2. Measure resistance between terminals 1 of HO2S harness connector and 43 of ECM harness connector.
    3. Measure resistance between terminals 2 of HO2S harness connector and 59 of ECM harness connector.
    Fig 1: Measuring Resistance Between Terminals Of HO2S Harness Connector & ECM Harness Connector
    G00883923Courtesy of HYUNDAI MOTOR CO.
    • Specification: below 1ohm 

    Does each resistance indicate continuity? 

    Yes: Go to next

    No: Repair open in harness.

  4. CHECK HO2S SIGNAL WAVEFORM
    1. Reconnect HO2S and ECM connectors.
    2. Warm up engine to normal operating temperature.
    3. Using Hi-Scan (Pro), monitor HO2S signal waveform.

    Does the HO2S signal switch from lean to rich or from rich to lean? 

    Yes: Proceed with ECM PROBLEM PROCEDURE  .

    No: Replace HO2S.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.