New member here. I really want to maximize my mpg in my new 2010 Yaris, and have been averaging a disappointing 30mpg on my first few tanks of gas. Can anyone give me several simple hints at saving gas in my automatic? Kind of regret not getting a manual, but what is done is done.
Welcome, bentjazz. If you're making short trips in cold weather, 30 mpg may be all you can expect to get until Spring and Summer come. I rented a Yaris automatic in New England for a week, and averaged 42 mpg for three tanks.
Keep your maximum speeds down - 55 or 60 mph on slower highways always beats 70 mph on the interstate. 40 mph on a frontage road will average 50+ mpg.
Coast as much as possible. Most people still have their foot on the gas half a block from red lights and stop signs. I start coasting to them 3 or 4 blocks away - in neutral, so my engine is turning 750 rpm instead of 1500 rpm.
Plan your routes to minimize stops. Even with our fuel-sipper 1NZ-FE engines, starting from a stop nets <10 mpg going to the next stop sign 2 blocks away. If you minimize those stops and starts, you can get that 50 mph cruising mpg, instead of that 8 mpg stoplight drag race wastage.
If your Yaris doesn't have an instantaneous mpg meter built-in, consider getting an Ultragauge for $60.
DFCO is when the computer turns fuel off entirely while you're in gear and decelerating with the throttle closed. There are a lot of conditions that the computer considers when it decides whether or not to DFCO, and without equipment to tell you it can be hard to know your car's DFCO behavior. If you do know it then you can save fuel when you're planning to slow down.
I used to just assume that it would always DFCO when above 1000RPM in gear with my foot off the gas, but reality is nowhere near as simple and I wasted a lot of fuel until I learned that.