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Even when babying the car, I'm getting about 3mpg less than I did when I was not babying the car previously. Air filter clean, new oil, 27k miles. Only thing I can think of is the spark plugs? I don't have the manual on me...what was the recommended spark plug change interval? I'm completely stock, so should I just go with stock plugs? What are stock plugs? O'Riley's and auto zone both give me different plugs when I put in my vehicle info.
 

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My guess is the temps if you are in a cold climate. I get in the 19-20 mpg range during the winter here in Ohio and 23-24 mpg range during warmer weather. I do many short trips and VERY little highway driving. I did take one long trip mostly highway a couple of summers ago and got 31.2 mpg on a 425 mile trip.
 

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It's the weather. Got mine in the summer was always at least getting 24 mpg. As soon as winter came I can't get much better then 20 mpg. Winter sucks summer forever!!! The damn cold also fudged up my sound symposer.
 

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My car drops 2-3 from an average of 26 when it gets cold, say less than 35-40F. I am not sure if it the winter blend, weather or a combo. I suspect temperature. Random warm day, 50-60F, mpg jump up
 

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I agree with everyone else, cold weather = dense air = more fuel to keep 14.7 x 1 ratio = less gas mileage. OP your stock plugs are good for 100K according to the manual so @ 27K you do not need to worry about changing them..

Component 2.0L GTDI EcoBoost engine
Engine oil filter* FL-910-S
Engine air filter FA-1908
Engine fuel filter Service for life
Spark plug CYFS12Y2 (100,000 mile service)
 

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Cold here near Philadelphia, temps yesterday morning are down to about 3 degrees. Even on 93 octane, I am averaging 23.7 mpg. During the summers when we see 90-100 degrees I really don't deviate much maybe just a 1 mpg increase!
 

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Don't forget your tires will drop some pressure as well in the colder air.

The TPMS triggers at something like 30-32? So even if you are still running the stock tires in a non-snow climate, if ambient drops from 85F to 55F you will have some pressure drop in your tires > higher rolling resistance > lower gas mileage.

Mark
 

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I agree with everyone else, cold weather = dense air = more fuel to keep 14.7 x 1 ratio = less gas mileage. OP your stock plugs are good for 100K according to the manual so @ 27K you do not need to worry about changing them..

Component 2.0L GTDI EcoBoost engine
Engine oil filter* FL-910-S
Engine air filter FA-1908
Engine fuel filter Service for life
Spark plug CYFS12Y2 (100,000 mile service)
Pressure plays a bigger part when it comes to 02 content, ideal gas law, temp and content are on the same side of the equation and proportional to pressure. Nevertheless, I am surprised the car is actually as sensitive as it is. Assuming pressure stays constant (which it doesn't) from 32-90F there is a ~10% decrease in oxygen content

Edit - hum, 10% is about the mpg decrease
 

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Pressure plays a bigger part when it comes to 02 content, ideal gas law, temp and content are on the same side of the equation and proportional to pressure. Nevertheless, I am surprised the car is actually as sensitive as it is. Assuming pressure stays constant (which it doesn't) from 32-90F there is a ~10% decrease in oxygen content
Could not agree more with you. Anytime we have high pressure and cold morning (42) here is cold lol the car runs a lot stronger compared to summer 95 degree days with low pressure and High humidity.
 

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I'm getting 16.9mpg and running on premium ATM. I live in FL and although it's been cold recently it is nowhere near northern US cold. This normal?
 

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I'm getting 16.9mpg and running on premium ATM. I live in FL and although it's been cold recently it is nowhere near northern US cold. This normal?
Not at all. How are you driving the car? Any mods? Are you using the screen in the car or manually calculating? What brand fuel?
 

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Hey everyone,

Be sure to check out this video for some tips on how to improve your fuel economy:

If you feel you're not getting the fuel economy you should be, I recommend contacting your Ford Dealer, as they're in the best position to diagnose. Feel free to shoot me a PM, and I'll see how I can help.

Nick
 

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I'm getting 16.9mpg and running on premium ATM. I live in FL and although it's been cold recently it is nowhere near northern US cold. This normal?
In FL too and I'm getting 26.7MPG using 93oct. I do about 40miles round trip daily at an average speed of 50MPH or so (<30 through city, ~60 on main drag). Mostly using Mobil/Exxon. I'm just under 5K miles on the car.
 

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So I took a road trip yesterday and today from Columbus Ohio to Cleveland for a nice trip to the Cleveland Clinic and noticed some interesting details with my own fuel economy. I have only ever used Shell 93 Oct in this car since new, 95% from the same station in the last year as it is new.

-Normally in summer time on a long trip with cruise control between 65-70 I can get 32-35 no problem.
-In general winter I average 25MPG in town and used to get 32-35MPG but haven't seen over 28 this winter except for bullet below.
-In early January I took a longer trip to Michigan in colder weather ( 0-20F ) with cruise control 65-70, and also got 32-35. I did reset KAM right before I left to test and it seemed to work great.
-Yesterday on my trip to Cleveland (-8 to 3F ) cruise at 68 I could NOT get above 25.5MPG - The tires were properly inflated and there was little to no cross-winds etc.
-Today on my trip back I filled up in Cleveland at a BP, drove back ( 15-20F ) and got about 28MPG.

Do you need to periodically reset KAM? There should be no way at 68 I am getting 25.5MPG - Just seems unacceptable.
I do have CPE CAI and Torries SCT 93B tune and an OCC ( that fills up a LOT in winter ).

I'm thinking resetting KAM periodically in winter might help? Thoughts?

I think last year I noticed the same and I did a KAM reset and this seemed to work wonder
 

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winter fuel mix
dense air
creature comforts (heated seats)
thick oil (cold)
long warm up periods (0mpg)
 
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