Subaru Fuel Economy 101

So if you have owned your Subaru through any winter driving season, you have come to appreciate how well the all wheel drive functions when the road conditions are at there worst.  One of the draw backs to all wheel drive is the potential for reduced fuel economy so it is especially important to keep your Subaru’s systems in tip top shape.  Also remember any increase in fuel economy comes with the added bonus of decreasing the volume of tail pipe emissions produced.  It’s a win win situation, save some money and lesson your cars impact on the environment.

Below you will find some tips and information on how to get the most out of every gallon of gas.

1. Check your tire pressure every month, a low tire can increase rolling resistance which equals a decrease in fuel economy. Adding to that an improperly inflated tire can potentially affect the vehicle stability as well.

2. Change the fluids in your vehicle at normal service intervals. Old fluids can increase drag. Another words it takes more horse power and fuel to spin through old motor oil in the engine, old gear oil in the differentials and transmission as well. Another added benefit of changing fluids on your vehicle is decreasing the possibility of component failure from inadequate lubrication.

3. Try to use the defrost function less in winter, and the air conditioning less in the summer.  Whenever you use the defrost the air conditioning compressor cycles on to help hydrate moisture off the windshield.(assuming your vehicle is equipped with air conditioning) now while this is a great feature, it is also large drag on the engine and will decrease fuel economy.  Consider using an anti fogging agent on the windshield to help decrease the amount of time you need to have the defrost on.  Keeping your air conditioning system in good shape is also a good idea to decrease the amount of ac compressor cycles thus decreasing the amount of drag on the engine.

4. Keep your Subaru properly tuned and serviced, and don’t ignore check engine lights or drivability symptoms. Worn spark plugs and dirty filters can contribute to a decrease in engine performance and fuel economy.  If your check engine light is on your car is trying to tell you that the computer has recognized a problem.  If your Subaru is running roughly you are definitely cheating your self at the pump.

5. Driving habits, yes the way you drive has a large affect on the overall fuel consumption of your vehicle.  Speeds under 65mph will yield better fuel economy than speeds over 65mph,shutting the vehicle off during extended periods of idling is also a great way to conserve fuel.

6. Clean out the garage and make room for your Subie .If you have a garage and it’s too full of stuff to park your car in, consider some organizing.  Parking your car in the garage during the winter will decrease the amount of time that the vehicle has to run prior to performing at its optimum, which will greatly increase fuel economy and reduce the volume of emissions coming out of the tail pipe.  Your vehicle has to reach a certain temperature in order to go into what is called closed loop, this is when the vehicles computer uses many points of live data to determine the proper amount of fuel needed to achieve the most power, performance and the best economy.  The higher the starting temperature of the engine, the quicker it can go into closed loop.  While this tip is more about your garage than it is car maintenance, its purpose is to be food for thought and a good excuse to organize your garage.

7. Try to be proactive about your car and its maintenance needs, not reactive. Remember each of us doing something, is much better than none of us doing anything.

Justin Stobb
All Wheel Drive Auto

6 Responses:

6 responses to “Subaru Fuel Economy 101”

  1. Tom Harris says:

    I find with the price of gas (regular compared to the 94 grade high test ), that I put in both my respective cars…ie wrx 2002 wagon/ Impala ss 94. that the LT1 5.7 litre (350)v8 gets better gas milage per dollar than the WRX..go figure….I travel to Kelowna from Vancouver dozens of time a year, I can just make it on 70$ of premium in the subie, 420km. My 80 litre chev cost 90$ (regualar gas) to fill and can make it there and back. go figure..although, in winter, there is no choice. Love the Subaru..

  2. MIke Stone says:

    Justin,
    Can you point me in the right direction? I had my mechanic proactively replace my factory battery on my 04 Sub Forrester XT and when I got it back the speedometer, tachometer, and odometer will not work. (I also had to reset clock and radio stations). I checked fuses- visually OK. He says he doesn’t know what to do. I have seen similar complaints on the internet, but no concrete answers. Please help.
    Thanks,
    Mike

  3. Blue B says:

    Thanks for your feedback, sounds like it may not be the best idea.

  4. Justin Stobb says:

    Actually you would want to install the fuse into the fuse holder in the engine compartment on the strut tower to disable the AWD.

    This electronically disables the AWD system. Now while I have had a few customers put this fuse in to avoid repairing the AWD system, you do alter how the car performs and remember the Subaru All-Wheel Drive is a safety feature as well. There is also the possibility of the transfer clutch solenoid failing from lack of use. Meaning that one day when you want the AWD back and take out the fuse it won’t work.

    Merely food for thought, you would pick up 2 to 3 mpg, depending on your driving patterns.

  5. Blue B says:

    I was wondering if it is ok to take the fuse out that engages the AWD in order to have 2WD and better gas mileage theoretically…any feedback on that? Thanks. Only in automatics?

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Written by Justin Stobb

Justin Stobb is the Owner of All Wheel Drive Auto, the premier Independent Subaru Shop in the North West with locations in Kirkland and Bothell Washington. Justin has been providing Subaru Owners (regardless of where they live), with tips and advice about their Subaru since 2006.