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System Inspection

Air leakage check
1. Check "Air intake system"
  Check for looseness, deterioration, or contamination on throttle body and gasket.
  
  Check for contamination, damage, or cracking on intake manifold, ISCA, and injectors.
2. Is there any leakage?
  YES
  
  Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  
  NO
  
  Go to "Fuel line check " procedure.

Fuel line check
1. Check "Fuel line system"
  Check for looseness of connectors on fuel line.
  
  Check for looseness, damage, or interference of vacuum hose on fuel line.
  
  Check for damage, leakage, or bending on fuel line pipe.
2. Is fuel line normal?
  YES
  
  Go to "Fuel line pressure check " procedure.
  
  NO
  
  Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.

Fuel line pressure check
1. IG KEY "OFF".
2. Disconnect a fuel pump relay.
3. Engine start and wait until engine stop. and then IG KEY "OFF".
4. Connect a fuel pump relay.
5. Connect a fuel pressure gauge to a fuel filter by a fuel pressure gauge adaptor.
6. Engine start and measure a fuel pressure.
  Specification: Approx. 3.5kg/cm²
  
  Fig 1: Checking Fuel Line Pressure Using Fuel Pressure Gauge
  Courtesy of KIA MOTORS AMERICA, INC.
7. Is the fuel pressure normal?
  YES
  
  Go to "COMPONENT INSPECTION " procedure.
  
  NO
  
  Check for clogging of the fuel filter.
  
  Check the valve in a fuel pressure regulator.
  
  (If it has a problem, fuel happen to be leaked to a return line.)
  
  Check the supply pressure of fuel pump.
  
  Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.