Have had my Ecoboost for about 3 week's now. Absolutely love the truck but the past 2 week's it's been getting horrible gas mileage. 2 day's after i bought my Ecoboost I took a 3 hour(all highway) trip to visit family. It got around 19mpg with a little less than 100miles on the odometer. On my way back home the mileage fell to around 17. Since I've been home I've been getting around 14 to 15mpg both highway and stop and go side street's that are typically 35mph-45mph. My main commute to work is half main roads and half highway. Once getting on the highway she rises to about 15-ish and hold's around there. I'm reading about everyone getting 18 + and I'm stuck around 14. Anyone else getting horrible mileage?

My driving habbits lately have been ***** footing and I'm still stuck around this mileage.

 

My mileage wasn't much to write home about for the first few thousand miles. Around the 5k mark it really picked up. Of course I drove the thing like I stole it at first. Overall I average mid 17s but I drive fast and hard, this is a good 3-4 over my 5.4L. Tonight I kept is slow and easy and was knocking off mid to low 20 pretty easily. A couple of questions.

-What gas stations have you been getting gas from? A change in supply could hurt economy of the quality is down.

-Ethanol quantity? Corn should be used to make whiskey not gas.

-Time spent idling?

-Into or against the wind?

Tomorrow switch your display to show the instant fuel usage and try to use the skinny pedal to keep it high. See how it does and give it a little more time.

 

In addition, I would figure in air temps. With the winter temps around here, I'm seeing a 2-3 mpg drop in my non-EcoBoost F150. The colder it gets the worse the mpg.

I idle very little. The truck warms up faster if I drive it.

 

mine gets 16ish in the city and 19/20 HWY. I have heard not quite the mileage that Ford advertised. But remember the advertised numbers are 4x2 on level ground.

 

How are you getting your mpg calculated? DO you have the message center on your tuck. If so did you reset the mpg once you got up to crusing speed on highway?

 

remember your driving habits, city driving will be poor mileage whether it be Eb, 5.0, hemi or whatver. Buds hemi gets 12 and dodge claims way higher numbers. If you think about it for any half ton to get 15-16 highway and almost 20 HWY while being able to tow 10-11k is impressive. Your other alternative is a diesel which will get you 12-14 all time and cost you 50-80 cents more per gallon.

 

sounds normal to me. Like you, I have a EB that is finicky and has only averaged high 14's since birth. Your driving situation sounds like mine. I guess we have factory duds while others are seeing 19-20mpg consistently.

 

i doubt somebody is getting 19-20 city I get that highway.

 

Temps went from 60-70ish down to about 20's to 40's. Has been a little windy around here lately as well,

Not sure about my gas quality but I have filled up about 3 or 4 times twice at the same station. and twice at 2 different stations, My last fill up i went to mid-grade gas instead. Around city I'm noticing it staying at 15.2 and it only goes up to around 15.6 once I'm on the highway. When I get onto the highway it takes me about 10minutes to get to work, maybe that's not enough time for it to calculate?

I'm going off of both my trip display and my gas mileage usage display on my center LCD.

Idle only at stop lights. Can't seem to shake why I went from 19mpg highway all the way to St Louis down to 15. I've been hammering on her pretty good at when I drive like that i expect low mileage but not when I'm taking it nice and easy. Have hit the reset button as well on my MPG and it always goes back to around 15.

 

The colder air should be denser, denser air has more oxygen, more oxygen = more power, more power should equate to less throttle to move the same weight.

The winter blend of fuel typically has less thermal energy so the vehicle is required to burn more to make the same energy (transferred into motion). That is where I think we are seeing the decreased mileage this time of year. I go through several thousand gallons of fuel per year and can almost pin-point the day in the fall that the station switches to winter blend, and then the day they switch back to the summer blend in the spring. Mileage changes accordingly with no change in driving habits.

 

With crap winter gas I'm getting 17-18 with mainly city driving. I don't see any problem at all getting 19+ in the city with the summer gas.

 

Hey everyone! This is my first post here so bare with me! I just bought my truck last week and it was a demo with 4 thousand on it. I guess my first mistake was buying Walmart gas.Since then I've averaged about 12 MPG on the highway it's around 14-16 mpg.
My highway speed was really crazy because I was REALLY moving at most of the time!
But..its still better then the 07 "toy"death trap I traded for!... but THATS another story!
You're Friend. Dave

 

Once in closed loop, the O2 sensors cause more fuel to be used to stay around stoich with the denser air.

 

This is true. Also, temperature is a huge factor. My Eco has < 1,000 miles but I was getting 19+ on the highway when it was 40 degrees. Same highway, same speed but at 5 degrees, I'm getting 17.5. Think of those big bearings, differentials etc. and the additional resistance when the weather gets cold. I have a ScanGauge and could see the increase in required horsepower due to the colder temperatures.

 

I have an eco fx4 screw with only 1k miles on it so far and i see about 14-15 mixed driving and i use the remote start alot. Its not great but it is about 1 mpg better than my old 5.4