Component Inspection

■ Check the Condition of HO2S 

1. Check HO2S for poor connection or loose terminal.
2. Check if HO2S is securely installed.
3. Is HO2S in good condition?

   YES 

   • Go to "Check the Signal Waveform of HO2S" as follows.

   NO 

   • Repair it and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ Check the Signal Waveform of HO2S 

1. IG "OFF". Connect HO2S connector.
2. Engine start.
3. With Engine at operating temperature, monitor signal waveform of HO2S with GDS.
   Fig 1: Screen Display - Normal Waveforms Of Front HO2S (Upper) And Rear HO2S (Lower) (Chassis Ground)

   Courtesy of HYUNDAI MOTOR AMERICA
   Fig 2: Screen Display - Normal Waveforms Of Front HO2S (Upper) And Rear HO2S (Lower) (Sensor Ground)

   Courtesy of HYUNDAI MOTOR AMERICA
4. Is the sensor switching properly?

   YES 

   • Go to "Check Fuel Filter" as follows.

   NO 

   • Substitute with a known - good HO2S and check for proper operation. If the problem is corrected, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ Check the Fuel Filter of Fuel Pump 

1. IG "OFF". Disconnect the fuel pump connector.
2. Start the Engine and wait until fuel in fuel line is exhausted. After the engine stalls, IG "OFF"
3. Remove the fuel pump assembly.
4. Check the fuel filter for clogging by dust, a foreign substance.
5. Is the fuel filter O.K.?

   YES 

   • 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.

   NO 

   • Substitute with a known - good fuel filter and check for proper operation. If the problem is corrected, go to "VERIFICATION OF VEHICLE REPAIR " procedure.