Last post on Jul 11, 2013 at 3:32 PM
You are in the Scion xA and xD
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Scion tC, Scion xB, Scion xA, Fuel Efficiency (MPG)
May 18, 2006 (1:48 pm)
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.
#190 of 508 Re: xa milage [rspellman]
May 19, 2006 (3:31 am)
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.
#191 of 508 Re: xa milage [cdoc]
May 19, 2006 (6:48 am)
May 19, 2006 (9:54 am)
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.
#193 of 508 Re: xa milage [rspellman]
May 19, 2006 (1:16 pm)
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.
#194 of 508 Re: Octane and mpg [aatherton]
May 22, 2006 (1:10 pm)
Sorry aatherton, everything I have read says there is absolutely NO BENEFIT from getting premium fuel. Your just wasting your money.
#195 of 508 xB benefits from high octane gas
May 27, 2006 (5:11 pm)
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.
#196 of 508 Reality on the gas.
May 29, 2006 (4:32 am)
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.
#197 of 508 Reality on the gas
May 30, 2006 (8:35 am)
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.
#198 of 508 Knock sensor, hp and mpg
May 30, 2006 (3:07 pm)
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.