I'm posting this in the Prius c forum though the topic surely applies to all cars. With fuel prices somewhat elevated (May 2026) and on their way to record heights, I've started looking deeper at improving fuel economy. There aren't likely to be any revelations here; just little improvements that weren't quite worth capturing previously. The challenge I'm making for myself is to use tools I already own (mostly a spreadsheet and some mapping apps) to make some money-saving decisions. I'm not interested in modifying the car or using an anti-social driving technique- besides, that's already been explored heavily in other threads. I looked at the driving I need to do today and found that I can save about $0.73 by driving alternate routes through the city at lower speed. The overall trip will be about two miles shorter, and it will be done at a higher fuel economy due to the lower speeds involved and I'll spend about seven more minutes driving it. So far, this looks worthwhile. I'm curious to learn if there are any good mapping apps which help the user to prioritize fuel economy over simple trip duration. It is officially time for that feature.
I haven't had any success with mapping apps, but then again I don't live where traffic can change to the point that a mapping app can point me to a route with less traffic on it. Hypermiling does help. I have gotten well above 40 mpg in my 40-mpg-rated Avalon hybrid by hypermiling. Basically, you push the accelerator until the ECO needle is on the line right between ECO and POWER, you get up to your acceptable top speed for when the engine will shut itself off (the Avalon will do that around 45 mph), and when it does you shift into neutral and coast back down to your acceptable lower speed. Then you put it in D and do it all over again. This pulse-n-glide technique causes the engine to be running either at its most efficient load or not run at all and to keep cycling between the two. I'd be interested in aeromods, but those really only help at higher speeds. Most of my driving is around town. As much as I hate the idea of riding my bike due to the fact that it's basically suicide with the way people drive these days, I'm thinking I really need to get back into it too.
If the object is to spend less money on gas, besides improving efficiency, consider also reduction of driving, and consolidation of errands.
That works for retired people but is not effective for the majority who still work using their vehicles or have a serious commute five days a week. Companies experimented with remote work but have largely dumped it due to the obvious efficiency losses and inability to judge work ethic and management potentials.
One thing that's helping me save money is owning multiple Prius and loaning them out for free, which usually leads to the person borrowing it filling the gas tank... Only bought one tank of gas so far in 2026. But when it comes to Prius C, I have one coming in for 100K mile maintenance and I'm wondering about the EGR system and if it ever gets clogged and requires the same amount of cleaning? Also what beyond spark plugs and Oil change and MAF sensor and throttle body? Got any links to the best thread for that?
I'd argue remote work was killed because of how much money companies have put into their real estate and the need to justify its existence. Whereas to Government agencies like here in Washington State it's way more efficient and is an enormous money saver, which has also reduced rush hour traffic. As for age, It really doesn't have as much to do with that as where you decide to live... People who don't like crowded noisy cities and live a significant drive from town are gonna spend a fortune in coming years because every time they need something they have to get in their car... As for me in the PNW I used to live rural and it was heartbreaking to see so many vacant lots with big huge trees growing on 'em get destroyed for new housing. But a year and a half ago I moved to within a 2-3 blocks of all the major stores and places to eat and the big trees in this neighborhood were mostly wiped out a century ago. Took me a while to get out of the habit of driving. But I'm more and more often having days where I don't need to drive at all. Also have way more tree pruning and gardening jobs that are just a short walk away. So grateful that I'm no longer required to get in my car if I need to go somewhere. It took some time getting use to a life at walking speed.
It can still be a consideration. A family that makes a shopping list that they go get once a week after coming home from work or that one of the working adults swings by and gets on his or her way home from work will use less fuel than one that goes to the store whenever they need an ingredient on the whim. Also making sure you have a valid payment method on you before driving is always helpful. Prius c Maintenance Schedule | PriusChat The only thing I absolutely disagree with is yearly/10,000 mile oil changes. This will destroy the engine before 200,000 miles. The manual says do 5,000 mile or 6 month oil changes (whichever comes first). If you're doing more than 10,000 miles a year than go with every 5,000 miles (at 95,000, 100,000, 105,000, etc.) If you're doing less than 10,000 miles a year then change every 6 months (every spring/fall equinox, or every summer/winter solstice.) The way I understand the manual is you can do yearly or 10,000 mile oil changes if you live in Pheonix, AZ and only drive on the highway on flat ground with no cargo box or trailer, etc. Sparkplugs: every 12 years or 120,000 miles. I don't think you need to do anything to the MAF sensor or throttle body unless you get a check engine light.
I think the general idea I'm chasing is that I'm going to add trips to my spreadsheet, and I'll do it in two ways. One is a prediction of savings for two different routes to the same destination. The other will be a record of actual results. I figure once I get a few trips of each route in there, I can use this to pick the most economical routes to various local neighborhoods. When I compare the prediction to the actual for today's trips, I see that the savings were a little short. I attribute this to the fact that the route selected by the computer (optimized for distance) included a couple of hill pulls- I could probably have done better by driving 10% more distance without the elevation change. Around the hill vs. over it. That just brings me back to wanting a friendly mobile mapping app that can be optimized for fuel economy rather than simple trip time or A-B distance. It's a tantalizing goal- let's burn a few watts on computation to prevent burning many more on transportation. It was a waste of time at $2.50/gallon. It's a curiosity while we're knocking on $5. It'll be pretty darn important when we hit $10.
