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Discussion Starter #1
Hey guys I just recently bought a 2017 eco boost premium from the local Audi dealership. When I went to the screen that keeps up with the MPG it was 13. Would this affect my gas mileage. Only had the car for 2 days and went through a quarter tank. Can anyone help me with this topic?
 

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Several questions come to mind:
  • when was the trip computer last cleared/set to zero?
  • Did this computation include a lot of idling time/ sitting in traffic, etc.?
  • how many miles for this sampling?
  • does this include time before you purchased it? Lots of times dealers let cars idle for extended periods with heaters or AC running, depending on who is using the car for demos, etc.
Lots of factors affect gas mileage, and I have found that the on board calculation is not always accurate. The only way to accurately check fuel mileage is reset trip meter, fill up but not beyond automatic pump shutoff , drive for a good number of miles before calculating (I would recommend 100+), refill at same location and gas pump(and fuel grade), and hand calculate total miles driven divided by total gallons to refill = true MPG. Also, use a good grade of fuel, preferably "top tier" quality, regardless of what octane you choose to use.

I'd do this a few times before getting too concerned about MPG.....

edit: I'd also recommend running out most of the present tank of gas and filling from a station with known good quality fuel before calculating MPG. Eliminate unknowns/variables.
 

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You can expect your Eco to get anywhere from 14mpg to 21mpg in city traffic, depending on how heavy your foot is. You will get anywhere from 22mpg to 35mpg on the highway, again, depending on how heavy your foot is. These cars' gas mileage HUGELY vary as you traverse the RPM range. The best ditty I've heard on the Ecoboost, is its either "Eco" or "Boost". Never both.
 

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Hey guys I just recently bought a 2017 eco boost premium from the local Audi dealership. When I went to the screen that keeps up with the MPG it was 13. Would this affect my gas mileage. Only had the car for 2 days and went through a quarter tank. Can anyone help me with this topic?
Had it for 2 days and gone through 1/4 rank, sounds about right. Tank only holds 15 gallons iirc,
 

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LOL, boost is the enemy of fuel economy. I usually drive fairly conservatively and I'm typically around 9.5L/100km (about 25 mpUSg). It doesn't take much aggressive use of the throttle to get that figure up to 12 (a little under 20 mpUSg). If you are generally aggressive on the throttle, I can see where that figure would drop even more. Throw in the aforementioned idling time at the dealer that you might not be aware of and you end up at your quoted number. As mentioned above, drive it well down to the bottom of the tank and fill it with your favourite fuel (I strictly use 91) and reset one of the trip meters and that will give you a better idea of what you're doing, noting that the dash is a little optimistic. I also run a spreadsheet based on calculated amounts.
 

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Discussion Starter #6
Several questions come to mind:
  • when was the trip computer last cleared/set to zero?
  • Did this computation include a lot of idling time/ sitting in traffic, etc.?
  • how many miles for this sampling?
  • does this include time before you purchased it? Lots of times dealers let cars idle for extended periods with heaters or AC running, depending on who is using the car for demos, etc.
Lots of factors affect gas mileage, and I have found that the on board calculation is not always accurate. The only way to accurately check fuel mileage is reset trip meter, fill up but not beyond automatic pump shutoff , drive for a good number of miles before calculating (I would recommend 100+), refill at same location and gas pump(and fuel grade), and hand calculate total miles driven divided by total gallons to refill = true MPG. Also, use a good grade of fuel, preferably "top tier" quality, regardless of what octane you choose to use.

I'd do this a few times before getting too concerned about MPG.....

edit: I'd also recommend running out most of the present tank of gas and filling from a station with known good quality fuel before calculating MPG. Eliminate unknowns/variables.
Im not sure when the computer was cleared I just got it the other day and I guess the previous owner had a heavy foot and their MPG was 13. There wasn't a lot of idling time or sitting in traffic. I drive maybe 5 mins in the city before getting on the high way to go to work. Work is about 22 miles away from my house. I drive to the gym which isn't to far from my house as well. This is my first mustang so didn't know about clearing the computer. I will try what you said the next time I fill up which should be this weekend.
 

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I usually warm it up until I see 135 on the cyl. head temp, then only start boosting it once the oil temp. reads normal and the trans temp hits 100. Some will say I'm babying her too much, but 10psi gets me away from the lights just fine. Consistently getting an average 22mpg city using D and running Chevron 91. Don't do much highway since the 101 widening project has turned it into a frickin sand/rock blaster! Love my car too much.
 

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Filled up today and drove home, about 60 miles of highway @65-70 mph, 30.4 mpg. Not bad for driving in crappy weather with snow tires and winter gas.
 

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its either "Eco" or "Boost". Never both.
Definitely the above. As soon as you get aggressive with the car gas mileage goes out the window.

I don't know about the 2017s, but my 2018 has a real time gas mileage monitor. If the 2017s have one you might want to check it out. Mine is usually maxed at 40 MPG while cruising and bottomed out close to 0 when I have my foot down. Personally I'm doing just under 21 MPG with a short suburban commute and a heavy foot.
 

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I would not rely on the computer indication of MPG for anything more than trend monitoring; they are notoriously inaccurate. The best way to compute fuel economy is to track miles driven over three tanks of fuel. Why three? Because different pumps click off at different times, and three fill ups will average out the differences. gatorneck's estimate of expected fuel economy is accurate. If your car is significantly different from that you should have it checked out.

I use the computer fuel economy indication strictly for trend monitoring. In other words, you can't rely on the accuracy of a given indication, but you can rely on it to indicate a change from "normal." As you get used to the car over the coming months note the computer's fuel economy indication under different driving conditions. Once you have an idea of what to expect watch for significant changes. A significant change in fuel economy can indicate impending engine trouble.
 

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I would not rely on the computer indication of MPG for anything more than trend monitoring; they are notoriously inaccurate.
True. I have kept a spreadsheet of all my purchases since delivery. I have just crossed 24K km (~15K mile) and the variance between my calculated fuel consumption and the dash is about 1.6L/100 km optimistic. In American, my calculated average is about 23.5 mpg while the dash average is 25 mpg. Too bad you guys didn't keep Imperial measurements after you kicked the British out, as my calculated fuel consumption on that basis is just over 28 mpg (makes me feel better!).
 

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I have a 2018 with the 10 speed auto and normally get 29 MPG in the summer although the computer says around 30-31 and 27 in the winter with snow tires and using the remote start.
 
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