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Home >> Mazda >> 2021 >> 3 Select, 4D Hatchback, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine (VINS 7, L, M) >> Poor Fuel Economy >> Notes
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Poor Fuel Economy: Notes

POOR FUEL ECONOMY (VINs 7, L, M) 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)
  • Clutch slippage (MTX)
  • Improper ATF level (ATX)
  • Brake dragging
  • 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)