MPG

Back in October of last year, I figured it was time to keep better track of my miles driven, fuel consumption and the like, maybe some patterns would emerge, maybe I could get a semi-accurate read on the fuel economy for my ride. 

First task: how to log the data.  I'd need to capture the miles driven, fuel cost, gallons purchased at the least to have the data necessary to calculate fuel consumption.  Here's my alternatives:

1. Old-style pen/paper.  Follow-up with a calculator, or abacus, or count on fingers, except when dividing.
2. Fancy-pants application for the mini-computer I carry with me most of the time. 

The low-tech solution seemed too hard, I just couldn't imagine writing legibly into a notebook more than twice before giving-up, so I went with the app.  After an exhaustive eight-minute search, I found a tool for my phone for mileage and fuel tracking: FillUp. Does not have fancy graphics, but it fits on my super cheap, low resource phone and works with minimum fuss.

MPG, says the EPA

Thanks EPA!

Out of the factory, Ford claimed claimed the Freestyle achieved 19/Mpg combined city and highway driving. Not sure what combination of city and highway, nor what qualifies as city versus highway. However it's calculated by the folks at the EPA, the numbers are 17 city and 22 highway, with a combined MPG of 19 miles per gallon. How does my Freestyle, after wondering the earth for better than 290K miles, stack-up?

Six months of painstaking (well, not really painstaking) data collection later and with 293K odd miles on the clock and I'm measuring about 19MPG after about 5,800 miles traveled. My typical trip into work is about 10 miles over country roads and 15 miles on the highway motoring along at 60 knots.  Even not-so-observant readers will note the outlier in late December.  My guess is this was the result of keypunch error and not me drifting downhill the prior tank.

Instant MPG

MPG on secondary roads

With Torque, I can collect the instant miles per gallon and on the highway the Freestyle can register as much as 25 miles/gallon when cruising on level road. Back roads result in much more variability, as can be seen with the instant MPG breaking 85 when the foot's off the throttle and the gravity does the work.

MPG on highway

What's very frustrating, and no doubt negatively affecting my mileage numbers is when the CVT transmission refuses to up-shift. No wrench light, but I'm stuck going 65 MPH at close to 4000 RPM, causing me to run at a little over 12 MPG. I can solve this problem by putting the car into N and drifting down hill, letting the RPMs drop to 2000, the putting the car back into D will result in more normal shifting  Something's wrong, but what?

Cost per Mile Driven: Cheap!

Stats from FillUp

Running the numbers, how does this work in terms of cost per mile? About $0.14 for fuel. I've spent about $1000 on various parts, add to that about $800 dollars of gas ($806.49 for those keeping tabs) has run through Freestyle an average cost of $2.46 per gallon: that puts me at a super-cheap $0.31 per mile operating cost. As I keep the Freestyle in service for longer, I'll be amortizing that cost over more miles, steadily reducing the per-mile operating cost, as long as I don't encounter anything too expensive on the repair side of things. However, the exhaust willneed to be replaced soon, so it looks as though per mile costs won't costs heading north at such a rapid clip.

Does Gas-Saving Maintenance Make Sense?

That also raises the question regarding other maintenance work generally associated with improving gas mileage. Should I bother? The air filter was replaced as part of the initial service of the car, but the spark plugs and fuel filter haven't been touched. I have a fuel filter on hand, as it may have been a culprit for another problem (it wasn't), so I can replace that soon.

Next thing to consider is the spark plugs. Changing the spark plugs means removing the intake manifold and a bunch of other parts to gain access. Considering the work involved, I'm not so sure that I would see much of a difference fuel efficiency: each 1% MPG increase would net me $8 dollars over the next 6 months, so I would need to see an increase of over 10% MPG (about 1.8 MPG) to get a 6 month ROI on my spark plug change, and that prices my labor at 0. While I might dig in and change the plugs for entertainment value, it wouldn't necessarily be economically reasonable.