Edmunds Answers

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  • avatar rickmn 05/05/08 10:10 pm PST

    You bet it is. If you put in a lower octane, the engine will have pre-ignition (ping). The knock sensor will detect that and retard the timing. That will decrease your pickup and gas mileage. The lower octane can also cause misfires which will set off your check engine light. The misfires load the catalytic converter with unburned fuel which causes it to run at much higher temps, which can destroy the converter. Need any more convincing?

    Source: 

Answers

  • MrShift@Edmunds 05/05/08 8:47 pm PST

    well the car's computer will adjust for lower octane fuel but really the whole point of buying the XT is to get that 225HP from the turbo, so if you degrade the performance (which you will) by using 89 or 87 octane, you are in reality not using what you paid extra for in the first place. Then just buy the X instead of the XT and save yourself $5,000 that way, rather than trying to save it on gasoline by robbing the XT of its horsepower using lower grade fuel.

    My two cents.

  • rickmn 05/05/08 10:10 pm PST

    You bet it is. If you put in a lower octane, the engine will have pre-ignition (ping). The knock sensor will detect that and retard the timing. That will decrease your pickup and gas mileage. The lower octane can also cause misfires which will set off your check engine light. The misfires load the catalytic converter with unburned fuel which causes it to run at much higher temps, which can destroy the converter. Need any more convincing?

    Source: 

  • orbit9090 08/26/09 2:38 pm PST

    Apparently, the TELESCOPIC steering wheel feature requires premium fuel - since it isn't available on the 87 octane models...I mean Subaru must assume that 'short & frugal' people exclusively buy the X model and 'tall & lead-footed' people exclusively buy the Turbo...Other than that, there's no reason not to include TELESCOPIC in every Forester trim level. In fact, the ONLY appealing reason to splurge for the XT is for the TELESCOPIC steering wheel feature...but hood scoops are sorta corny on a station wagon.

    Source: http://www.subaru.com/vehicles/forester
    /...

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