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 drive 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.
