Besides idle curiosity is there a reason to track fuel consumption and purchases?
Perhaps for tax reporting for a POV used in a business? Because otherwise ISTM that fuel cost and consumption is one of those things, like the weather, that we can bitch about but not really affect to a meaningful degree.
Of course there’s a purpose. It’s true that fuel cost can’t be individually controlled but certainly consumption is a factor.
Fuel consumption is one of the main factors I use in making a purchase decision in the first place and at least always on the back of my mind while I’m driving and does affect how I drive to reduce inefficiencies (in time or consumption or whatever).
I may be an outlier in that regard but I suspect there’s at least a decent minority of people who do the same. It’s true that expectations need to be tempered by the type and purpose of the vehicle (e.g. a big truck for hauling lots of cargo vs a daily commuter) but that helps set the level - it doesn’t entirely remove the consideration.
If it turned out consumption was significantly greater than advertised, I would be pissed and consider not purchasing another vehicle from that manufacturer.
For me, the app does it for me. With our Subaru, I don’t track beyond seeing what crappy gas mileage I got on each fill-up (it displays that). Of course, our Subaru is just sitting now so it is getting great fuel mileage. Haven’t added fuel since we purchased the EV.
One reason I do it, is to make sure everything is running how it should be. If I notice a big enough difference in mpg then I start checking things like tire inflation and other things. It can be an early sign that something is not quite right with your vehicle. Also, if you have more than one vehicle it definitely helps you decide which one to use for a given trip or circumstance.
//i\\
Hmm. Very interesting.
I bought the car I bought for whatever combo of reasons and I’m stuck with however efficient or inefficient it may be until it’s time to buy something else 3 or 6 years hence. If when I bought it I was expecting e.g. 25mpg and it turned out to be 23 or 27 in actual usage over a year I’d simply chalk that up to the falsities inherent in the EPA mileage standards; not to any sign of failure nor skullduggery unique to that make or model.
Once the specific car is a given, I drive only by reference to time, with no thought to fuel consumption. Faster is better (within the confines of speed limits and such), and less distance by artful navigation and combining errands is better too.
The car has a cumulative MPG computation that I reset every couple of months after a fill-up. It’s pretty consistent (within a couple MPG) despite varying city/highway mixes that change at random based on my activities that week. IMO the MPG value would need to change drastically (>25% delta?) before that constituted actionable evidence of malfunction. Meanwhile the car’s other health monitoring computers would have sounded an alert long before that.
Modern cars, even fairly basic models of modern cars, are already doing a lot of the watching for you. Leave the work to them; they’re good at it.
Diff’rent strokes.
I’m squarely in your camp on this question.
Obviously fuel consumption is going to be a factor when I’m researching and then purchasing a car, but once I own it, I might track MPG for a couple of fill-ups (or check the car itself). Once it’s been established that the car is going to get x MPG with slight variance for longer or shorter trips, I am no longer concerned with that figure. If I bought a car that was advertised as getting y MPG, but it actually got y-3, it would not be a big enough reason to immediately trade it in for a different model.
Some folks have a need to track stuff that definitely wouldn’t make sense for others. I have spreadsheets of lots of things and my wife thinks I’m crazy. I would tend to agree with her as I look at some of the stuff I’ve tracked over my life. I’m learning to let a lot of this go but I understand why someone might track their vehicles gas/electricity consumption.
I too track many things. But generally temporarily as I’m starting or stopping something, not for the long haul.
E.g. when I first became diabetic I tracked weight, blood sugar, meds, exercises, and every bite of food. Every day, multiple times per day, for a couple years. A non-trivial commitment.
That stopped a decade ago once I’d developed a reasonable gestalt on how much to eat of what and how much exercise to get.
From here on out I operate on rules of thumb and “close enough good enough”. My quarterly blood draws and PCP visits are feedback enough. More isn’t better; it’s just useless compulsive wankery.
IMO YMMV.
For my first few cars I knew generally how many miles I’d get per tank so it would be obvious if something was off. My most recent ICE would tell me how many miles until the tank was empty. Same thing
The primary reason is that I do not get OCD about things. I like those pictures not aligned! So tracking fuel economy is the one thing were I get obsessive, and I like playing with the resulting data. The secondary, and much more practical reason, is that the fuel tracking app also lets me track the maintenance schedule, and ICE vehicles are all about maintenance.
For my Tesla I have a subscription to Teslafi. For $50/year I don’t have to write down anything, but I can query the data as much as I want. For example, in response to the fuel economy discussion upthread I determined that on winter tires I get 3.5 miles/kWh and on regular tires I get 3.8 miles/kWh. Once per year it is useful when I need to deduct my business mileage, so I can quickly search for all trips to or from my rental property. This year that saved me about $20 in taxes!
If anyone wants a one month Teslafi trial instead of the normal two weeks, you can enter my username as your referral code. If you end up buying a subscription, I’ll get $5 off my next renewal.
Idle curiosity, mainly, in our case. Though a notable decrease in mileage could indicate a problem.
The app we use also allows us to enter stuff like maintenance, which could be useful.
Also, if we’re curious about how many miles we drive in, say, a given year, that info is readily available.