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Fuel System Trouble in General: Inspection

FUEL SYSTEM - TROUBLESHOOTING CHART

Trouble and possible cause Corrective action
1. Insufficient fuel supply to injector 
1) Fuel pump does not operate.  
  Defective terminal contact Inspect contact, especially ground, and tighten it securely.
  Trouble in electromagnetic or electronic circuit parts Replace the faulty parts.
2) Decline of fuel pump function Replace the fuel pump.
3) Clogged fuel filter Replace the fuel filter.
4) Clogged or bent fuel pipe or hose Clean, correct or replace the fuel pipe or hose.
5) Air is mixed in the fuel system. Inspect or retighten each connection part.
6) Clogged or bent air breather tube or pipe. Clean, correct or replace the air breather tube or pipe.
7) Damaged diaphragm of pressure regulator Replace.
2. Leakage or blow out of fuel 
1) Loose joints of the fuel pipe Retighten.
2) Cracked fuel pipe, hose and fuel tank Replace.
3) Defective welding part on the fuel tank Replace.
4) Defective drain gasket of the fuel tank Replace.
5) Clogged or bent air breather tube or air vent tube Clean, correct or replace the air breather tube or air vent tube.
3. Gasoline smell inside of compartment 
1) Loose joints at air breather tube, air vent tube and fuel filler pipe Retighten.
2) Fuel saucer gasket air tightness fault Correct or replace the gasket.
3) Inoperative fuel pump modulator or circuit Replace.
4. Defective fuel meter indicator 
1) Defective operation of fuel level sensor Replace.
2) Defective operation of fuel meter Replace.
5. Noise 
1) Large operation noise or vibration of fuel pump Replace.
NOTE:
  • When the vehicle is left unattended for an extended period of time, water may accumulate in the fuel tank. Fill the fuel tank fully to prevent this.
  • In snow-covered areas, mountainous areas, skiing areas, etc. where ambient temperatures drop below 0°C (32°F) throughout the winter season, use a water removing agent in the fuel system to prevent freezing fuel system and accumulating water.
  • When water is accumulated in fuel filter, fill the water removing agent in the fuel tank.
  • Before using water removing agent, follow the cautions noted on the bottle.