Prius c only getting 43mpg avg

You can be sure that people getting 60 mpg are not doing 70 to 75 mph, at least not on level ground. I'm sure the recordholders at Top 20 - MPG Record Holders | PriusChat and 1000 mile tank highway challenge by Japanese hybrid drivers | PriusChat are doing at LOT more than just having properly inflated tires.

For fun, maybe you should watch the video at Wayne's Newest Vid | PriusChat. Unfortunately, you can't see the HSI bar in it.

More videos at http://www.cleanmpg.com/forums/showthread.php?t=43315&page=5 (it'll be a spoiler if you visit that page. I haven't had time to watch Wayne's presentation.)

I can't speak to your readings and whether the values are the same in both directions. If not, there could be head/tailwinds and net elevation changes. Use Google Earth can give you an elevation profile of a route between 2 points! | PriusChat to figure out the elevation change.

BTW, in CR's tests, they got 48 mpg on the highway in the Prius c. Last page of http://www.consumersunion.org/Oct_CR_Fuel_Economy.pdf describes their test,

 

Poolgod, I would also expect better than 43 MPG from your C2. Your miles per trip (31) and the outdoor temps in Louisiana (50 to 75 degrees) should have a positive effect on mileage. Driving above 70 MPH does hurt, but as you indicate, that is not done most of the time.

As already suggested, get your tire pressure checked. If you are doing highway driving, low tire pressure will kill your MPG. Also mentioned is the quality of the gasoline that you are using. With only 1,200 miles on the car, you probably have only used a single gas station. Gas with a high (any) ethanol content will lower mileage.

You did not describe how you calculated MPG. The only accurate method is to divide miles driven since last fill-up divided by the gallons pumped into the tank. Any calculation made by the vehicle ECU is just an estimate (typically too high). You really need three fill ups (3 MPG calculations) before drawing conclusions about good or bad mileage.

It is unlikely that you have a roof rack on your new car, but just note than roof carriers ruin fuel mileage. It is also unlikely that there is something "wrong" with your C2, but there is a simple check you can make to eliminate the possibility of brake rotor drag. After driving at least ten miles with little use of the brake pedal, get out of the car and place a hand on the wheels near the center hub (not on the wheel covers). If a wheel is hot to the touch, it indicates that the brake pad(s) are riding on the rotors. I have bought a lot of new cars and twice I have found a dragging brake pad.

I have owned a 2010 Gen III Prius and a 2010 Honda Insight and they both had a life time average of 48 MPG. They were both driven thru cold Indiana winters which are big mileage hits compared to driving in Louisiana. I have never hyper-miled or become distracted watching displays. I always accelerate briskly. My ECO driving consists of minimizing the use of the brakes and not acceding 70 MPH. So my experience is that it is not hard to match the EPA ratings with a hybrid. My new Prius C4 will be at the dealership on Monday, so it will be interesting to see how it stacks up to the Gen III and the Insight in terms of MPG.

 

Without a location posted its hard to say if you are working with winter blend fuel. That plus cooler temps and high speeds with a brand new car should equal lower fuel economy. I wasn't getting over 52mpg when my car was new last March but after it broke in, summer blend fuel came online and the temps rose into the 90s+ my mpg shot up to the 60s.

Yours is just one of the many posts we expect to see as winter rolls in. It happens every year.

 

Your mileage will jump a bit after break-in. Ours was around 3,000 miles on the odo. Just drive normally. Easy on the gas when you start after stopping and keep out of the red as much as possible on the meter. Pulse and glide does work to an extent but just driving normally and taking it easy on the acceleration seems to do just fine. We were averaging 48 mpg for the first couple of thousand miles and now have about 54-55 mpgs. Weight in the car does make a difference as we have noticed when carrying chairs and equipment in the back. Hang in there, you will learn to get the best out of your C with experimenting and experience.

 

Hurray. Tire pressure the culprit

 

My pressure was low to and for a few days I just assumed it had to have good pressure, I just got it from the dealer right?

 

I have bought a lot of cars and seldom is the air pressure in the tires correct when the vehicle is delivered. The worst problem is that the pressure is not consistent from one tire to the next. It is as if the goal is just to get a tire over a minimum pressure, and anything over that is OK. Remember, tire pressure should be checked at least twice a month and frequent checking is critical when the season (temperature) is changing.

 

Yep. There will be some gain to the tires and car breaking in. See Tire Tech Information - Tire Rolling Resistance Part 3: Changes to Expect When Switching from Worn-Out to New Tires. Some of the increase later down the road will be due to the reduced circumference of a worn tire.

That said, some of the OP's gains will be negated by winter fuel, falling temps and rain on the road. He should see it all come back and then some in spring.

 

When the day comes to replace those tires be sure to get the low rolling resistance tires.

 

It sounds like it was an issue, but if the OP expects values like 60 mpg, he's going to have to do more than properly inflate his tires.

 

Yep he will have to become a hyper miler practicing all the techniques outlined in this video.

 

Aye and be careful to choose the right LRR tire. Not all are created equal.

 

How do you differentiate LRR tires?

 

That's the problem. You can't without reading controlled tests by companies like TireRack.com and anecdotal information posted by other owners. There is not a robust system for certifying rolling resistance or fuel efficiency claims. Even the system in the EU and Japan is based mostly on manufacturer honesty. In North America we don't even get that weak assurance. That is why some of us try our best to stay on top of these tests so we can tease out the best from the worst.

 

I have Yokohama Avid and have no problem getting the identical brand when it is time.

 

I heard tires can make or break you on the mileage game.

 

That is correct. There is a 4+mpg difference between the LRR tires we know of. The AVID S33D is somewhere between the best and worst in terms of mpg. They are not the best as a replacement choice, however.

 

Mine were at max sidewall pressure when delivered... I ended up letting air out of then when I first checked them a month later.

 

What are the Top Choices?