Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Scion MPG-Real World Numbers



  • aathertonaatherton Posts: 617
    Here are the tanks that I have recorded on my manual xB in the 2000 miles since I got it:

    33 mpg - 3 tanks
    Breaking in with constant acceleration and deceleration in 4th and 5th gear, on long drives on mostly country roads, some suburb, very little city, and no Interstate, using 3/4 throttle, shifing at 2000 rpm, not exceeding 3000 rpm.

    40 mpg - 1 tank
    One continuous drive, mostly country roads, some suburb and very little city, no Interstate, shifing at 2000 rpm, not exceeding 3000 rpm.

    35 mpg - 1 tank
    Normal daily driving in suburbs and city, no Interstate.

    32 mpg - i tank
    Normal daily driving in suburbs and some city, no Interstate, but with more acceleration by shifting at 3000 rpm and driving more aggressively

    The mileage is entirely under my control. I can get 40, or 35, or maybe even 25 mpg, depending on where and how I drive.

    If I wanted to compete at every stop light, lead the pack all around town, and eat up the beltway at 80 mph, the xB would aquit itself admirably. I have tried it rather often, and it is great fun. But is is very bad for the mileage.

    However, in consideration of the price of gas, I like to savor the ability of the VVT to take shifts at 2000 rpm, and I lay back from the pack in traffic.
  • aathertonaatherton Posts: 617
    The xB engine can benefit from high octane gas. The manual says use 87 octane or better. The "better" refers to the knock sensor. The high compression engine detunes itself for regular gas. The ECU (engine control unit) slows the ignition advance when it senses pre-ignition due to low octane gas. Slowing the advance reduces power, which requires more throttle and gas to compensate.

    If you drive gently, the engine will see no benefit from low octane gas. But if you drive hard, using full throttle, high rpms, and cruise at high speeds, the engine can benefit from premium gas. It will make it's full designed power, it will accelerate faster, it will use less throttle pedal, will make more power under full throttle and high rpms, and will use less gas.

    However, a tank of premium costs $2 more than a tank of regular. If premium gas saves 2-3 mpg, it is a wash cost-wise. The benefit of premium gas is not in the wallet, it is in the seat of the pants from better response and more power under full throttle and high rpms.
  • aathertonaatherton Posts: 617
    "... if you drive gently, the engine will see no benefit from low octane gas."

    That shoud read:
    "... if you drive gently, the engine will see no benefit from HIGH octane gas."
  • rspellmanrspellman Posts: 4
    Hi all I just bought a 2005 silver xa, on my first complete tank I averaged 36 mpg in mixed city and freeway driving( L.A. freeway traffic jam conditions),for a car with only 300 miles on it im very happy.I traded my Suzuki Aerio for this car,I liked the Aerio but questionable reliability reports caused me to trade it for the Scion.The Scion is a vastly superior car you can feel it the moment you sit in the vehicle.Looking forward to many happy miles ahead. Incidentally it's not just young people that buy these cars im 58. :)
  • cdoccdoc Posts: 41
    I bought mine last March, and haven't gotten below 35 mpg overall, mostly back roads driving. I've also found, since it revs so high, being very gentle on the gas makes the car drive smoother. I keep the rpms no higher than 2000, except in 5th gear, and I start in first by pushing on the gas very gently. And I love how high I sit inside.
  • rspellmanrspellman Posts: 4
    Sorry 2006!
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,626
    You might want to rev it up more. 2,000 is kind of lugging the engine I think. It is designed to rev up and is happy to do so.
  • rspellmanrspellman Posts: 4
    :) I just completed a 180 mile joy ride in my xa,mostly freeway some fast mountain and all with air conditioner use. The verdict 40.8 mpg! I have read complaints that the car is underpowered and rough riding I disagree the ride is much better than my Suzuki Aerio,that car had alot of power but this car is perfectly adequate.
  • carfanatic007carfanatic007 Posts: 267
    Sorry aatherton, everything I have read says there is absolutely NO BENEFIT from getting premium fuel. Your just wasting your money.
  • aathertonaatherton Posts: 617
    Sorry carfan, what you read is saying "there is no benefit to high octane gas IF your engine can't use it." We have all been reading that for decades. For that reason, I would never put high octane gas in our Buick Regal or Mazda truck. Waste of money.

    But the xB owner's manual says the xB engine can use high octane gas. Read it -- it says use 87 octane "or better". With its high 10:5 compression ratio, the xB engine uses its computer management system to retard the ignition on 87 octane gas whenever you use full throttle or high rpms, to avoid pre-ignition (aka knocking or pinging). Retarding the ignition reduces power. If you don't drive hard, you won't mind 87 octane. But if you are trying to pass a car on a two-lane road and need the most power the engine can make, you will want full ignition advance from high octane gas.
  • js34js34 Posts: 4
    Sorry but aatherton's right. No monetary gain but perhaps performance gain.

    I've owned 4.6L with 10.0 compression and knock sensors, and 9.0 without KS.

    The 10/KS required 93 octane and did horribly without it. Always better mileage with it but still cost me more $ overall.

    Is this absolute lab-tested proof? No. But aatherton's explanation is sound.

    I'm treating the car as it was designed. High fuel economy. There's no sense ricing the hell out of it (including 93-103 octane) to tweak out the extra 5 hp.
  • aathertonaatherton Posts: 617
    I have gone to using 93 octane all the time. I generally drive easy. But maybe half-dozen times a day, I like to boot the car up a hill or scoot ahead of someone, using heavy throttle and high rpm. At those times I want to enjoy the full power that the great little engine is capable of, without the inteference of the knock sensor.

    On the usual ten-gallon fillup, 93 octane costs an extra $2. I fill up once a week, so if I make use of the high octane 6x7=42 times per tank, the cost per kick is 200/42 or less than 5 cents. Cheap thrills for this 63-year old.

    The only possiblity of monetary gain from 93 octane is high speed cruising. If at 80 mph on 87 octane the knock sensor should be working continuously to prevent maximum ignition advance, then the engine would use less throttle at that load if it were able to burn 93 octane and make more power. Less throttle means less gas.

    In this ideal situation, can 93 octane then pay for its extra cost? People have reported that trips at 80 mph result in poor sub-30 mpg. Suppose that is not only due to the high wind resistance of the box, but also to the knock sensor reducing power on 87 octane and causing more throttle to be used to maintain the speed.

    Suppose using 93 octane at 80 mph reduced the amount of throttle enough to save 2 mpg. On a 300-mile tank, that would save .7 gallons of 93 octane, worth about $2. That is the same as the extra cost of the gas. So in reality, it's a wash, with no monetary gain from high octane.
  • aathertonaatherton Posts: 617
    The new little BMW F800 motorcycle has 800cc and 85 hp with a high compression ratio of 12:1. The review in the BMW News says:
    "... according to BMW, the fuel mileage is 47 mpg on premium fuel, with the option to convert to regular with a loss of 2 hp and a few mpg."

    Unlike the xB, the cheapest BMW motorcycle does not have costly sophisticated electronic engine management that senses knocking on the fly and retards the ignition as needed. To use 87 octane, the BMW bike's engine computer must be converted (i.e. "flashed" or reprogrammed) by the dealer.

    If the penalty is proportional to displacement, the xB would lose almost 4 hp and 5 mpg on 87 octane gas.
  • aathertonaatherton Posts: 617
    "... If the penalty is proportional to displacement, the xB would lose almost 4 hp and 5 mpg on 87 octane gas."

    This would only occur at high load on the engine - full throttle demanding full power, hard acceleration, high speed riding. Puttering around town, or crusing down the road, using only a little of the engine's potential, there would be no penalty.
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,626
    I've tested regular and premium on the Scion xA and wasn't able to record any MPG difference beyond statistical variation. I did feel more spunk in the engine though, but that was just butt-o-meter, and may be an illusion, I don't know. My toyota factory rep said to run a tank of premium through the engine every now and then, so I do that.
  • aathertonaatherton Posts: 617
    "...I've tested regular and premium on the Scion xA and wasn't able to record any MPG difference beyond statistical variation. "

    You would have to run a lot at high load, full throttle, high rpms, high speed, to see the difference. In ordinary driving, not invoking the knock sensor, there is no difference to record.
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,626
    yep, that's the only way I drive, mostly full on. I really didn't notice any difference in MPG, perhaps because I was enjoying what felt like a bit more power. I may try another test sometime and will let you know.
  • rspellmanrspellman Posts: 4
    From my house in Azusa Ca. to Primm Nevada sometimes caught in traffic,50% air conditioner use,most of the time above 70mph, 87mph top speed ---- 40mpg!
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,626
    that's great!

    I just did the 8,000 mile averaging, for all kinds of driving, all kinds of weather, all kinds of gasoline....and the answer is: 34 mpg!!
  • aathertonaatherton Posts: 617
    Manual xB with 3,000 miles. Been using Chevron 93 octane for the past three fillups, so it's all unmixed 93 by now. Just filled up today at my usual gas station after 268 miles of driving in and around Louisville. Mostly errands on suburban streets, some interstate hops downtown, and one 50-mile trip in the countryside. I drive at a normal pace, using minimum necessary rpms, with occasional 3/4-throttle bursts to accelerate around people or get up hills.

    The fillup was 7.29 gallons, for 36.75 mpg.
Sign In or Register to comment.