System Inspection

■ Check the fuel filter for restrictions 

Remove the fuel pump and check filter for debris and/or clogging of the fuel supply line.

■ Check the fuel level 

If you run out of fuel significantly on ramp, it may be a factor of degradation of the fuel pressure.

■ Check low-pressure fuel supply line leakage and restriction 

Low-pressure fuel supply line damage and/or restricted blockage can be a fuel pressure drop factor.

■ Check Fuel Pressure Regulator 

• Check Fuel Pressure Regulator performance by measuring voltage and current.
  1. Using an oscilloscope, measure voltage by using and connecting channel A (+) voltage probe to High Side and channel A (-) voltage prove to Low Side.
  2. Measure operation current by using Low Current Sensor Module.
     Fig 1: Screen Display - Engine Idle After Warm Up

     Courtesy of KIA MOTORS AMERICA, INC.
     Fig 2: Screen Display - Approx. 2000 RPM

     Courtesy of KIA MOTORS AMERICA, INC.
  3. Are all listed items normal?

     YES 

     • Go to "VERIFICATION OF VEHICLE REPAIR " procedure.

     NO 

     • Recheck the listed items from this troubleshooting guide steps, and replace or repair as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.