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Ford Fiesta Real World MPG

134 messages,  Last post on Apr 25, 2013 at 9:52 AM

You are in the Ford Fiesta Forum.

What is this discussion about? Ford Fiesta, Fuel Efficiency (MPG), Hatchback

Messages Page 13 of 14

#114 of 134 Better Gas Mileage by obkt

Aug 26, 2012 (7:13 pm)

There's a new gas station in town called Alon. Used to be Fina. They are selling gas that's 100% free of ethanol. 87 octane. I live at 4K feet so 87 is like mid range. I've picked up 3-4 mpg driving around town. 36mpg with the AC on. 2011 Fiesta SE hatch with auto transmission.

#115 of 134 Re: Fiesta rental [xwesx] by xwesx

Aug 26, 2012 (9:51 pm)

Replying to: xwesx (May 24, 2012 2:40 pm)
I finally took the plunge and purchased a Fiesta! I decided to save myself a few grand and purchased a 2011 SES Hatchback, optioned out exactly like I wanted (except the color), with manual transmission. It had 13,980 miles at my initial fill.
 
I purchased it Thursday afternoon, then we immediately took it on a camping trip to Palmer (about 320 miles south). After my first full tank, which was almost entirely highway (running 70 the whole way with four passengers and loaded to the gills with our camping gear), I put in 10.1 gallons after 394.5 miles, which calculated to 38.86 MPG. The readout said 38.9. I thought that was great, especially considering the load and a gnarly headwind we took for about 60 miles through the Alaska Range.
 
We put another 82 miles on it driving locally in the Palmer area, and put 2.1 gallons in it after that, netting just over 39.
 
Finally, coming home today we came out with 36.9, driving the entire distance (336 miles) home in steady rain. Considering the added resistance and the slight gain in overall elevation, I was quite pleased with the trip.
 
Had we taken our Forester, we would have seen 12 mpg less every step of the way, which means we saved a solid $40 (paid ~$3.80 per gallon).

#116 of 134 Re: MPG accuracy [hackattack5] by gimmestdtranny

Jan 22, 2013 (11:49 am)

Replying to: hackattack5 (Jan 10, 2012 3:50 pm)
I think the system uses a fuel sample measuring device on post fuel pump. Computer controlled of course which will measure various factors including speed of vehicle, position of accelerator pedal, rpm etc. This info is determined by (I assume) using a sample ratio of a predetermined quantity of fuel being instantaneously used. i.e. It can update itself ongoing to allow for the ability to show current average usage.
There are many parameters that could result in optimistic or pessimistic readings ranging from temperature of fuel to actual calibrations of the software measuring device that could be programmed either by honest mistake or deliberate manipulation.
 
My Honda ST motorcycle has a fuel usage computer and while I know it is more rare, its computer actually shows pessimistic readings. I always get better miles per gallon than it ever shows. I suspect they designed it that way so that you are inclined to refuel sooner rather than later and running out.
 
And I have checked it on brand new OEM tires, since tire wear is another parameter that influences distance travelled when using the car's own odometer and computerization if equipped with an onboard fuel usage computer...and affects the numbers a lot more than most would think. As the tires wear, diameter becomes less and odometer starts showing more miles traveled than actual. GPS would help an owner determine the affected percentage at any given time once they create a base line for their odometer potential error. Naturally, this is best done when car is new on new OEM tires. If you ever stray from OEM tires, then again the profile and sizing among tire makers of tires that state the same size as OEM, sometimes are quite different. Again, this is very evident when buying new bike tires. But absolute same potential with cars.
 
 Just as an aside info to whomever might be interested...be it in cars or bikes, any electronically controlled fuel injected car's fuel pump emerged in the gas tank (which represents basically all of them now, use the fuel to cool the fuel pump in operation. Always refueling before reaching 1/4 tank is a good idea for fuel pump longevity because the more gas that is in there to cool, the cooler it runs and longer it will last. This is a bigger issue in hotter climates of course. Owners who routinely don't refill until they are on fumes or constantly drive around adding 5 or 10$ at a time (most students, haha) unfortunately will get less pump life and probably end up replacing one prematurely and will never realize it was totally preventable.
 
I know this is the real world MPG thread, but am curious how these dual-clutch automatics are standing up? Anyone you know or have read online about that have put a LOT of miles on them and had zero longevity issues? (assuming the fluids are changed at the requisite and very lenient (IMO) mileage of every 150000 miles?

#117 of 134 Re: MPG accuracy [gimmestdtranny] by phill1

Jan 22, 2013 (12:05 pm)

Replying to: gimmestdtranny (Jan 22, 2013 11:49 am)
Seriously, was this Post for real? More likely a "thesis" for a PHD Degree. Worrying about the longevity of a dual clutch automatic transmission and possible fluid changes up to 150000 miles? Are you considering the purchase for Police or Taxi use? LOL

#118 of 134 Re: Ford Fiesta Real Time MPG [phill1] by gimmestdtranny

Jan 22, 2013 (12:27 pm)

Replying to: phill1 (Jan 30, 2012 7:41 pm)
edit: after reading your quick to insult post #117, I was tempted to remove this one, but decided it might be useful to someone else who might actually appreciate knowing the difference in autos and their efficiency potential.
 
One reason (but is only one of potentially many) is that the dual-clutch tranny in the Fiesta does not suffer the parasitic losses that your conventional hydraulic tranny with torque convertor that the Rio uses. I believe this is one reason, if not probably the primary one they decided to use a dual clutch set up in the Fiesta and Focus.
 
But what I would like to know as per my question at the end of my post above...is about longevity vs cost to own/repair. I wonder if anyone has gone 250000 or more miles with nary a hiccup? Naturally, any use in city would be the bigger test since the tran would spend more time shifting and clutch engaging than a user who drives for 100's of miles at a time out on the open freeway with it engaged in one top gear and rarely shifting except maybe for the odd hill. I suspect that computer and clutch pak servos etc are all quite expensive. I think with VW or Porsche dual-clutch trans they don't sell you parts..they sell an entire assembly, read huge bucks.

#119 of 134 Re: MPG accuracy [phill1] by gimmestdtranny

Jan 22, 2013 (12:18 pm)

Replying to: phill1 (Jan 22, 2013 12:05 pm)
 
Phil said:
Seriously, was this Post for real? More likely a "thesis" for a PHD Degree. Worrying about the longevity of a dual clutch automatic transmission and possible fluid changes up to 150000 miles? Are you considering the purchase for Police or Taxi use? LOL
 
Pardon me then... I will never take you seriously or make a helpful reply to another of your repetitive posts again. You have always indicated a passion for details, repetitive repetitive details...yet when someone comes along with a few bits of info that a person could use to good advantage, you get on their case???????
 
Some people would prefer to insult than learn. You decidedly fall into the former category. No wonder you rub others the wrong way from time to time. I've read a LOT lately. This seems to be your curmudgeonly way.

#120 of 134 OK by pf_flyer HOST

Jan 22, 2013 (6:44 pm)

Let's get back to the cars and stop making each other the discussion OK?
 
Thanks for your cooperation and participation!

#121 of 134 Re: MPG accuracy [gimmestdtranny] by xwesx

Jan 24, 2013 (7:55 pm)

Replying to: gimmestdtranny (Jan 22, 2013 11:49 am)
I've heard multiple mentions of the fuel pump longevity vs. fuel level issue in the past, and I'm wondering why that would be the case. Why would manufacturers even put the fuel pump in there in such a way to allow normal fluctuations of the fuel levels to cause damage to the pump?
 
That doesn't make any sense at all.

#122 of 134 Re: MPG accuracy [xwesx] by gimmestdtranny

Jan 24, 2013 (8:14 pm)

Replying to: xwesx (Jan 24, 2013 7:55 pm)
So you have never known a manufacturer to design something to fail.... nicely out of warranty?
 
I presume that the expectation is that most owners will refuel before pump temps get excessive enough that it will fail within warranty periods.
 
Even low fuel lights are conservatively triggered to come on with tons of warning. Many cars can go well over 60 miles or more before running out. So with 2 or 3 gallons still sloshing around is probably still a reasonable heat sink.
 
Excessive heat is the enemy in so many aspects of different components, whether they be electronics, metallurgy, tires, oil, batteries and everything in between. Many items are designed with a duty cycle..( a simple transformer based soldering gun for example, or an inexpensive oil less air compressor) and rely on cooling periods between use in order to not self-destruct.

#123 of 134 Re: MPG accuracy [gimmestdtranny] by phill1

Jan 25, 2013 (7:12 am)

Replying to: gimmestdtranny (Jan 22, 2013 12:18 pm)
So sorry, and I certainly apologize for upsetting you with my sarcastic remark. Perhaps readers appreciate elaborate scientific data in regards to everyday driving conditions. I will remain mute and add no further comment to this thread as I promised I would do the same after being expelled from the Kia Rio5 one as well for hurting another Posters feelings. Cheers

Messages Page 13 of 14

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