Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

2008 Kia Rio Base, AutomaticFACTORY OEM SERVICE PROCEDURE

Component Inspection

Visual Inspection.
1. IG "OFF"
2. Disconnect HO2S (B1/S2) connector.
3. Check that HO2S (B1S2) is contaminated or damaged by foreign materials.
4. Has a problem been found?
  YES
  - Go to step 2.
  NO
  - Substitute with a known-good HO2S (B1/S2) and check for proper operation.
  - If the problem is corrected, replace HO2S (B1/S2) and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
Check ECM/PCM.
1. IG "OFF".
2. Connect scan tool and Engine "ON".
3. Select simulation function on scan tool.
4. Simulate voltage at terminal 2 of HO2S (B1/S2) signal connector.
  
  Fig 1: Scan Tool Display - Simulate Voltage Of HO2S (B1/S2) Signal Connector
  Courtesy of KIA MOTORS AMERICA, INC.
5. Does the signal value of HO2S (B1/S2) change according to simulation voltage?
  YES
  - Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  NO
  - Substitute with a known-good ECM/PCM and check for proper operation.
  - If the problem is corrected, replace ECM/PCM and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  NOTE: There is a memory reset function on scan tool that can erase optional parts automatically detected and memorized by ECM/PCM.
  Before or after testing ECM/PCM on the vehicle, use this function to reuse the ECM/PCM

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.