Hey guys, I bought my prius in 2010(august) and love it! My first tank I got around 560mpg and since then it slowly been getting worse and im now down to 420ish per tank. Granted, my driving area has changed from city to hwy. I commute with this car 45miles one way to work daily at an average speed of 75mph while on the hwy(38miles of the trip). Is speed the major issue? Cold weather? Mix of a bunch of stuff? Mike
Speed and weather the issue? YES, among other things. I speculate that it's easy to get great mpg's when the car is new because we tend to drive a new car carefully, especially during break-in. As we become accustomed to it, we start reverting to old habits or not being so careful to extract higher mpg's. I'm guilty of it. Read some of tips under the Fuel Economy thread - you'll find lots of tips and ideas from many people that I found very helpful. The main thing is to slow down to get your mpg's back up.
Sounds like the weather and the increase in average speed are both 'helping' to cause this. 420 miles per tank is still about 45MPG---depending on when you fill up, which isn't unreasonable for a 'V', on the highway, during the winter months up there in the Bay State. Check your tire pressures (Your 'see no evil' TPMS will not illuminate untill there's at least a 5-psi dip in your tire pressures) and try moderating your heater settings. Good luck!
- tyre pressure (~1psi per 9°F). Most people don't even have it at recommended pressures during the summer.. so assuming 68°F, by the time you're at the freezing mark, you've lost 4psi in the tyre. That's about a 10% loss in air pressure from recommended pressures - winter fuel blend - less petroleum, more additives to minimise freezing - longer warm-up period (esp. if it's parked outside) - heater (you want the heater, it'll idle at traffic lights instead of shuttiing off. I'll sometimes just shut off the climate control at the lights. 30 secs won't make a difference since I'm bundled up anyway. This way, the engine can shut off and I'll fire up the heater once I'm moving)
I notice in the rental Prius's that I drive, if I drive it like I stole it, the mileage goes way down :rofl: A good benchmark is to head into the city and find a route where you get in some stop & go driving that you determine the pace without traffic influencing your mileage. A late night neighbourhood with stop-signs would work fine. Note what you can do for averages then use a few of those test runs as a benchmark if you suspect your mileage dropping for some unknown reason. As other's have stated above, tire pressure, then that winter blend gas our big Gov pushes upon us are factors in what level of gas mileage you can obtain. I have found tire pressure to be a huge influence in any car's gas mileage. I set my rental Prius pressures at 40psi front & rear. That gives me a 4psi rise after the tires warm up with my driving style, which is still under the max pressure rating of the tire when it is warm. I can take a Gen 2 and get 53.8mpg city/hwy driving around Minneapolis with the A/C running :rockon: Mike
