FixVault

Poor Fuel Economy: Notes

POOR FUEL ECONOMY (VIN Y) DESCRIPTION AND POSSIBLE CAUSE

Troubleshooting item Poor fuel economy
Description  
  • The fuel consumption is high compared to the customer's expectations or the previous fuel consumption.
Possible cause  
NOTE:
  • The perceived poor fuel economy condition has two causes; the vehicle conditions and how the driver uses the vehicle. Especially, it relies heavily on how the driver uses the vehicle.
  • Engine oil malfunction
    • Improper engine oil level
    • Engine oil contamination
      • Improper engine oil viscosity
      • Improper engine compression
      • Ignition system malfunction
      • Improper engine coolant level
      • Improper tire air pressure
      • Improper tires, wheels (large size, irregular size)
      • Improper ATF level
      • Brake dragging
      • EGR system malfunction
      • Engine operation time is longer than traveled distance
      • Vehicle is driven in congested traffic frequently
      • Vehicle left idling for long periods
      • Amount of fuel injection increases
      • Vehicle is carrying excess items (luggage)
      • Frequent acceleration/deceleration
      • Frequently driving uphill
      • Travel distances are short (engine does not warm up)
System wiring diagram  
  • Not applicable
Connector diagram  
  • Not applicable