Ugly mpg with 1.5..Help

[Mark S.]

Ever since putting larger tires on my MPG hit the basement! 22. It REALLY killed gas mileage.

Larger, heavier tires require more power to spin up. The tendency is to step harder on the pedal to get the same rate of acceleration you had before installing the larger tires. This is one case where I feel ECO mode would really help with fuel economy, but you’d have to be willing to accept reduced acceleration.

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[Jrl]

Larger, heavier tires require more power to spin up. The tendency is to step harder on the pedal to get the same rate of acceleration you had before installing the larger tires. This is one case where I feel ECO mode would really help with fuel economy, but you’d have to be willing to accept reduced acceleration.

Also Mark you have the difference in tire size affecting the mph not being equal to the original stock size . IMO

 

[davidg4781]

And a second update. I had to go out of town for a work meeting, about 1.5 hours away. I filled up, reset the trip mileage, and hit the road. I came back at 27 mpg. This was at mostly 75 mph, some 65 mph. A bit of spirited driving and some Eco mode.

 

[KidWiff]

And a second update. I had to go out of town for a work meeting, about 1.5 hours away. I filled up, reset the trip mileage, and hit the road. I came back at 27 mpg. This was at mostly 75 mph, some 65 mph. A bit of spirited driving and some Eco mode.

27 mpg at 75 mph?? That sounds more like it!

 

[KidWiff]

I thought i'd revisit this thread based on my experience yesterday. I just had a 375 mile trip over the weekend (actually all in one day to be exact). I filled the BS Heritage (1.5L) with fuel Saturday evening and while at the gas station set the trip odometer at zero, drove it home and then ran out for a quick errand later Saturday night.

Started the car up Sunday morning Odometer read 1235 miles. (can't recall the exact miles on the TRIP odometer but it couldn't have been more than 10 since refueling) and the trip mpg was at 24. I should say i normally average around 27.5 mpg, according to the computer and when doing the math at the time of fill-up.

Took the ride from western CT to my daughter's in Boston, some errands there (city driving) and then back home. Weather was clear, no rain... a bit windy in sections... i could feel the BS getting bounced around by gusts of wind, on the highway, a couple of times. Speeds were generally between 65 and 75 (mostly 70-75 to keep up with traffic). Almost the whole trip, with the exception of about a 4 mile stretch of stop & go, was moderately heavy traffic but smooth sailing. I engaged the auto stop/start during that time we were stop & go.

My odometer read 345.5 miles driven when i got back home and, according to the mpg figure on the dash once all was said and done, i had gotten 31.5 mpg. I still have 1/4 tank (approx. 4 gallons?) remaining that says i theoretically have another 126 miles before empty. 4 gallons for 126 miles works out to 31.25 mpg so... it might be right on the button. Sort of amazed that little 3-banger got that kind of mileage maintaining those speeds over 345 miles (but not complaining!!)

I'm going to do the calculations when i fill up today or tomorrow and see if that same mileage works out right. I was not going especially easy on the throttle for this trip but i was smooth in my acceleration. Bottom line... I can see squeezing 33/34 mpg out of the little BS as very do-able with the right driving style and mix of city/highway driving.

EDIT: the overall trip was 345 miles, not 375 as originally posted.

 

[Mark S.]

I thought i'd revisit this thread based on my experience yesterday. I just had a 375 mile trip over the weekend (actually all in one day to be exact). I filled the BS Heritage (1.5L) with fuel Saturday evening and while at the gas station set the trip odometer at zero, drove it home and then ran out for a quick errand later Saturday night.

Started the car up Sunday morning Odometer read 1235 miles. (can't recall the exact miles on the TRIP odometer but it couldn't have been more than 10 since refueling) and the trip mpg was at 24. I should say i normally average around 27.5 mpg, according to the computer and when doing the math at the time of fill-up.

Took the ride from western CT to my daughter's in Boston, some errands there (city driving) and then back home. Weather was clear, no rain... a bit windy in sections... i could feel the BS getting bounced around by gusts of wind, on the highway, a couple of times. Speeds were generally between 65 and 75 (mostly 70-75 to keep up with traffic). Almost the whole trip, with the exception of about a 4 mile stretch of stop & go, was moderately heavy traffic but smooth sailing. I engaged the auto stop/start during that time we were stop & go.

My odometer read 345.5 miles driven when i got back home and, according to the mpg figure on the dash once all was said and done, i had gotten 31.5 mpg. I still have 1/4 tank (approx. 4 gallons?) remaining that says i theoretically have another 126 miles before empty. 4 gallons for 126 miles works out to 31.25 mpg so... it might be right on the button. Sort of amazed that little 3-banger got that kind of mileage maintaining those speeds over 345 miles (but not complaining!!)

I'm going to do the calculations when i fill up today or tomorrow and see if that same mileage works out right. I was not going especially easy on the throttle for this trip but i was smooth in my acceleration. Bottom line... I can see squeezing 33/34 mpg out of the little BS as very do-able with the right driving style and mix of city/highway driving.

You may have had a nice tailwind. Mileage over a single tank is not very accurate, especially if you are using only the dash indicator. To get the most accurate figure you should track miles driven over three tanks and hand compute. This will average out most of the factors that can affect mileage.

 

[KidWiff]

You may have had a nice tailwind. Mileage over a single tank is not very accurate, especially if you are using only the dash indicator. To get the most accurate figure you should track miles driven over three tanks and hand compute. This will average out most of the factors that can affect mileage.

OK, so.... Filled up today and the hand calculated MPG worked out to 30.032 mpg
So, while not the 31.5 that the trip computer calculated it was solid number, i think, for moving a large brick on wheels at 65-75 mph during the course of a 345 mile trip. YMMV

 

[Wild Bronc]

I drive at 60 mph on mostly highways and very little in town driving and average 32.5 mpg with my 1.5 liter BS. I never warm the engine more than 1 or 2 minutes before I hit the road.

 

[V8 Yankee]

My 2021 BS big bend 1.5, automatic, 10700k TSO done on rear brakes and rear end differential replaced. I am only getting 13 mpg. 95% of driving is in town under 40 mph. I tried 2 tanks premium and I used eco mode for one tank with no noticeable mpg changes.. Recently I went 160 hwy miles at 70 to 75 mph and 82 miles in town under 40 mph on 15 gals in normal mode ...avg 16 mpg by my math. Should it be better than that?
Car instruments showed about the same same mpg avg. But 15 gals of in town driving only gets me 13 mpg...what is going on..? I read where people are averging 21 to 25. What can I do?

I never read through the thread to see if someone responded. Here is my take, first check your Fuel Bias Setting using Engineer Test Mode. You can find the thread on that subject using those keywords. You need a accurate calculation to change the fuel bias. There's a very good tutorial on changing your factory fuel bias. First you will need to calculate actual mpg after 3 or 4 tanks of fuel before changing the settings.
Second, do you use Auto-Stop? I know its a love/hate feature but it saves fuel. If your engine is running and the wheels are not turing you are getting ZERO MPG.
City driving is the worst, highway on the other hand is where you should be in the 25 plus range. Of course there are so many varibles to get 25 plus, it comes down to a few main things. Maintain the speed limit, use cruise control, higher tire pressure and topography. Weather is a factor also as a stiff headwind makes a huge difference on the highway. If you have passengers or cargo that is going to lower mpg so take that in account.
Other than that there is no reason why your BS should get 25 or more mpg. In my case I am getting a 34500 avg of over 33 mpg. I've done some mods to enhance the suggestions I wrote above which really made a difference. On strictly hwy driving I get 44-45 mpg at 55. City anywhere from 22 to 30 depending on traffic ond stop lights. If you try the suggestions I wrote you will get better mpg, the city part is a tough one though. The Broncos are just not made for good mpg and city milaege is the worst. Good luck.

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