Not Getting Mileage like what it says

Yeah it's normal. It's call winter. You're starting the ICE at 40-60F instead of 70-90F. It takes more gas to warm up the ICE. When first drive, it's EV powered. By the time the ICE can power the wheel, you've depleted the HV battery. The ICE has to recharge the HV battery and drive the wheel and use more gas. It's cold outside, engine cools much faster when it stops. It takes a lot more gas to keep it warm. ICE needs to stay warm to get good mileage. Cheapest way to get your mileage back is to block the lower front grill and the gaps around the hood and the fender. You won't get summer mileage but at least it's a couple to a few mpgs. Even my plugin is suffering. I'm down to 85mpg instead of 100+mpg.

 

We just did a round trip from San Diego to Big Bear at 42 mpg. That's going 75-80 mph plus the climb/descent. For 50 mpg I would think speed limit everywhere and egg under foot is in order? Too much work, I'm good with 42-44 (best tank is 44 mpg with 2800 miles)

 

'at first it started to come about 49 48 but now it not even 51.' isn't that getting better?

 

The EPA rating is an estimate only. It is not dogmatic rule. As they say "your mileage may vary".

 

That said, I am right at EPA estimate even with the recent frigid weather here in PA where temps are getting into the 20's overnight. I park outside, so it runs the ICE quite a bit until it is up to temperature.

I'm still on my second tank though, first tank was 50.5 calculated which is actually pretty close to what the car's computer said. Car now says 49.5, but this week is colder than the last. I'll fill-up tomorrow and get a second reading. I drive mostly highway, which has been wide open during this holiday time. I expect my mpg to go up once traffic is back and I am in more stop and go.

Either way, I'm excited to go 500+ miles on 9.5-10 gallons compared to my old car that was only getting 250-300 miles on 12.5 gallons and 93 octane. Not nearly as fun as my previous 300hp twin turbo bmw, but these days the extra cash in my wallet is nice.

 

We have about 64,000 miles on our Prius. Right now the display states 49 mpg which is about 45.5 true mpg.

Summer time the display would read, with the same type of driving and speed, 55-57 mpg, for about 52-53 true mpg.

This is with winterized gas and 10% Ethanol, in Oregon 10% Ethanol is required by law in gasoline for auto use all year long...

If you achieve a true 50 mpg in your Prius during the winter in the northern states or Canada you are driving too slow to be on the roadway.

al

 

i got 58mpg on my last tank, although, it has been unseasonably warm here, i AM driving too slow to be on the roadway.

 

There should be a rule that you can't post your MPG without posting your average speed The other night I got 53 mpg at 64 mph, I scored a good tailwind... Has anyone thought of a small computer controlled sail for the roof yet?

Mick

 

Yep. OP should read http://priuschat.com/forums/other-c...uth-about-epa-city-highway-mpg-estimates.html.

 

I've use 6 hamsters house in the trunk with all the food and water they need as my 3rd drive train...I pretty confident I drive much fast than your average Prii owner for sure!

 

My 2010 lifetime mpg is 56.35 as measured at the pump , and the lifetime average mph is 40, as recorded at each tank. 66 tanks of gas, 30,000 miles. 1.5 years owned.

 

lt = 61, mph = 27, 30K, 4 years.

 

I'm getting 51 on the first tank of my 2011 Prius, in Denver, where the last few days have been colder than normal. Trip to work is cold and uphill, usually in the low 40s. Return trip is warmer and downhill, easily 62-65.

I'm not really trying to get the absolute best mileage, but I am experimenting with ECO vs normal mode to see what impact it has for me and my driving habits. Also alternating highway commutes with surface streets, as the highway trip is only 13 minutes, and the surface streets about 25 - that's less to find the "right" route than to see how MPGs improve as the car warms up.

Thus far, I'm REALLY happy with the mileage, and can't wait for spring temps to see what it can really do!

 

50 mpg over an entire cold winter is hard to do, and I doubt even possible in really cold winters. Not having short drives and blocking the radiator help a lot.

 

The Prius is a remarkable machine, and it will deliver the predicted mileage. But everything must be "right." With over 50K miles experience, I have learned:

Tires are important (low rolling resistant tires and correct pressure); Temperature (cold weatherhas a negative impact - good discussion above); Speed (72 mph on Interstate is ideal); Short trips are killers); city driving from stop light to stop light saps mileage (a long steady drive from 35-45 mph will yield 65 plus mpg); rain and water standing on the street has a tremendous impact; and obviously ... snow.
I believe the 51 mpg is a threshold somewhat like the sound barrier. You will notice no other car can achieve it (other than EV's). The Prius will do 51 and better, but everything must be spot on the optimum conditions. If I understand it correctly, the EPA "estimate" is a calculated number, and I assume they use all the favorable conditions in the calculation. Manufacturers would cry foul if the estimate was lower than actually achievable.

Every day, I marvel that the Prius is as comfortable, reliable, care-free; roomy, quiet, and frugal on the gas. My other vehicle has many of the same qualities ... but it gets exactly 1/2 the mileage. For that very reason, my other car only has 7500 miles on the odometer in a year and a half.

 

Not even close --- the Japanese cycle is a lot closer to ideal. IMO the single greatest flaw in the EPA test cycle is no ambient cold data.

 

One of the thirty minute city test cycles in the EPA test is done at an ambient temperature of 20°F.
See Detailed Test Information (click "detailed comparison")

 

51 is pretty good for winter. So I've got a few baseline questions Do you have 15" wheels, what tire pressures do you run, what is your average speed for the tank of gas? If you have a smartphone you can use m.fuelly.com to easily track your mileage, pretty handy. Have you thought about a block heater and blocking your lower grill?
Mick