No. 14 Poor Fuel Economy: Notes

2008 Mazda 6 s Sport, 4D Hatchback, StandardSECTION Notes
WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
DESCRIPTION & POSSIBLE CAUSE

14 POOR FUEL ECONOMY
DESCRIPTION  Fuel economy is unsatisfactory.
POSSIBLE CAUSE 
  • Contaminated air cleaner element
  • Variable intake air system malfunction
  • Engine cooling system malfunction
  • Improper ATF level (ATX)
  • Weak spark
  • Poor fuel quality
  • Erratic or no signal from CMP sensor
  • Clutch slippage (MTX)
  • Variable tumble system malfunction
  • Improper variable valve timing control system operation
  • Improper coolant level
  • Inadequate fuel pressure
  • Spark plug malfunction
  • PCV valve malfunction
  • Brake dragging
  • Improper valve timing due to jumping out of timing chain
  • Contaminated MAF sensor
  • Improper engine compression
  • Exhaust system clogging
    WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system:
    • Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.
    • Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE REPAIR PROCEDURE" and "AFTER REPAIR PROCEDURE" described in the repair information.

      (See BEFORE REPAIR PROCEDURE .)

      (See AFTER REPAIR PROCEDURE .)

    RENDER: 1.0x

    NO RELATED

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    When to See a Mechanic

    Stop DIY work and contact a certified mechanic immediately if any of the following apply:

    • You smell fuel, burning insulation, or see smoke.
    • Brakes feel soft, pull hard to one side, or make grinding noises.
    • The engine overheats, stalls repeatedly, or misfires under load.
    • You are missing required tools, torque specs, or safe lifting equipment.
    • You are not confident in the next step or safety outcome.