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Home >> Kia >> 2003 >> Rio Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1166: Lambda Bank Control Limit >> Test Procedure
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Test Procedure

  1. Turn ignition off. Connect Hi-Scan Pro/Kia Data Pro Scan tool or equivalent to OBD-II Data Link Connector. See Figure . Turn ignition on. Monitor for other DTCs. If other DTCs related to front or rear HO2S, fuel system, EVAP system or ignition system are set, do all repairs associated with those DTCs before continuing with this procedure. If no other DTCs are set, go to next step.
  2. Check vacuum hoses for splits and proper connections to engine (primarily Positive Crankcase ventilation (PCV) and Idle Air Control (IAC), throttle body, intake manifold and brake booster vacuum hoses). If vacuum hoses and hose connections are okay, go to next step. If vacuum hoses are found split, damaged or disconnected, repair or replace as necessary. Go to step  14 .
  3. Start engine and let it idle, disconnect vacuum hose between PCSV and EVAP canister, with valve not operating check for vacuum at PCSV. Vacuum should not be present. If no vacuum is found, go to next step. If vacuum is found at PCSV (possible failure at PCSV or circuit), perform diagnose and repairs according to DTC P0441, DTC P0444 &/OR DTC P0445  . After repair go to step  14 .
  4. Turn ignition off. Release fuel pressure. See FUEL PRESSURE RELEASE - EXCEPT OPTIMA under FUEL SYSTEM - DELIVERY in SYSTEM & COMPONENT article. Install fuel pressure gauge at fuel rail. See FUEL PRESSURE (RIO) under FUEL SYSTEM - DELIVERY in SYSTEM & COMPONENT TESTING article. Fuel pressure should be 46-51 psi (320-350 kPa) @ idle. If fuel pressure is as specified, go to step  7 . If fuel pressure is too high: go to next step. If fuel pressure is too low: go to step  6 .
  5. Turn ignition off. Release fuel pressure. See FUEL PRESSURE RELEASE - EXCEPT OPTIMA under FUEL SYSTEM - DELIVERY in SYSTEM & COMPONENT article. Disconnect fuel return line hose from fuel rail and blow through line towards fuel tank. If fuel return line is restricted, repair or replace return fuel line as necessary. Go to step  14 . If return fuel line is okay, replace fuel pressure regulator. Go to step  14 .
  6. Start engine. Allow engine to idle and clamp fuel delivery line before fuel rail and check for fuel pressure to rises. If fuel pressure rises, replace fuel pump. Go to step  14 . If fuel pressure does not rises, check on-line fuel filter and fuel pump pick-up screen for restriction. If filters are okay replace fuel pump. Go to step  14 . If fuel filters are faulty, repair or replace as necessary. Go to step  14 .
  7. Return vehicle to original condition. Start engine. Allow engine to idle until reaches normal operating temperature for more than 10 minutes. Using Hi-Scan Pro/Kia Data Pro Scan tool or equivalent, monitor front and rear HO2S voltage signal waveform. See Figure . If HO2S voltage signal switches from lean to rich or rich to lean over 6 times for 10 seconds. go to next step. If voltage signal waveform is not as specified, temporarily install a known good HO2S and check for proper operation. If problem is corrected, replace HO2S sensor. Go to next step  14 .
  8. Remove front and rear HO2S from vehicle, check HO2S for contamination, deterioration or damage. If HO2S is contaminated, deteriorated or damage, replace HO2S. Go to step  14 . If HO2S is okay, go to next step.
  9. Disconnect ECM harness connectors, also front and rear HO2S harness connectors. Thoroughly check for loose, bent, corroded connectors terminals. If connectors terminals are okay, go to next step. If connectors terminals are faulty, repair or replace as necessary. Go to step  14 .
  10. Return vehicle to original condition. Start engine. Check exhaust system for leaks, cracks or loose connection (primarily at exhaust manifold, catalytic converter around rear HO2S etc.). If no exhaust leak is found, go to next step. If exhaust leak is found, repair exhaust leak as necessary. Go to step  14 .
  11. With engine running, check for engine RPM decrease when disconnecting each fuel injector harness connector in sequence. Measure decreasing RPM at all 4 cylinders. If no engine RPM is change or only a small engine RPM change is notice, check for possible cause, repair as necessary. Go to step  14 . If engine RPM changes even at all 4 cylinders, go to next step.
  12. Allow engine to idle until reaches normal operating temperature. Using Hi-Scan Pro/Kia Data Pro Scan tool or equivalent, monitor MAF sensor voltage signals. Voltage should be 0.2-0.8 volts @ idle. If voltage is as specified. Problem is intermittent, check for proper connections at MAF sensor and ECM connectors. Go to step  14 . If voltage is not as specified, go to next step.
  13. Remove spark plugs and inspect plugs tips. Check for abnormal spark plug tips color, contamination and damage. Compare plugs to each other. If a spark plugs are faulty, find possible cause, repair as necessary. Go to next step. If plugs are okay, go to next step.
  14. After repair, return vehicle to original condition. Clear codes using Hi-Scan Pro/Kia Data Pro Scan tool or equivalent. Verify repairs by driving vehicle and monitoring for pending codes. If DTC is set during test drive, follow appropriate DTC test procedure.
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