OK, so what's the trick?

So, from above:
up tire psi
avoid running on battery power alone

You are being killed by defrost idling, but without a garage it is unavoidable, I suppose.

Take heart: we averaged 50 mpg our first year in spite of a tank with a 39.7 mpg in the winter. Our averages by season: winter 46.2, spring 51.2, summer 51.4, fall 51.7. This second winter should beat the 46.2 of last year, but not reach the other 3 seasons. My weather is roughly similar to yours in Wichita, and our commute is a real mpg killer at 1.5 miles. We do garage the car at home, so we only defrost for daytime frozen precip away from home.

Study the Tao of HSI by Hobbit. Here is the link: HSI

 

The thing that jumped out at me was the heating. That will kill your mileage until the cabin is fully warmed up to your setting. I have a short commute, so I only heat it enough to keep the frost off the windows, since it wouldn't really get warm before I get home anyway. You have a longer commute, but keeping it a nice comfortable (for shirt sleeves) 70'F is forcing the engine to stay on, even when you think it might be off. Turn the heat off when you come to a stop light to allow the engine to really turn off at least for those periods, try setting it to 67'F (you are wearing a jacket, right?), or else just wait for April to come around.

Tire pressure of 38/36 would get you most of the benefit you need without sacrificing the feel. You can go up to 40/38 if you want (or higher) but you start hitting the law of diminishing returns. 34/32 is too low though.

Otherwise commute distance is good, timing the lights is good. It sounds like you're pretty much on the proper track of accelerate normally and brake lightly. Your expectations are reasonable, but not with putting that much heat into the car interior.

 

While I have successufly used Pulse and Glide (70 mpg tanks, in a 2nd Gen, with aero mods, 15 inch tires, on a 23 mile one-way commute, in 80 F weather) I tend to think its a bit of an difficult technique to master to get better mileage.

So, as a beginner, with only 1/3 of your driving in suburban secondary roads, its probably best to hold off pulse and glide until you are getting in the 50's during the summer time...

Indeed, one experienced Prius driver did a paper at Hybridfest demostrating he was getting better mileage not doing Pulse and Glide, but his hold speed mileage was well below mine and others proven pulse and glide mileage (approx 74 mpg pulse to 40 , glide to 35 ).

Read up on SHM, or supper highway mode first. If you get into slow highway traffic (48 to 54 mpg) you can get into the 70's mpg during that time.

 

Concur w/all of the above. Yep, when idling to defrost, the OP is getting 0 mpg that entire time.

Agreed about limiting heater use although avoiding it might make things uncomfortable for the OP. See http://priuschat.com/forums/gen-iii...937-poor-winter-fuel-economy.html#post1215787 for my notes about heater usage.

(Since I have no 3rd gen) John1701a at http://priuschat.com/forums/gen-iii...-car-in-history-in-winter-14.html#post1249224 notes that "The new ECO mode allows the engine to remain off all the way down to a coolant temperture of 114°F."

I'm assuming you have no means to monitor coolant temperature so just look at my earlier post and yes, definitely consider grille blocking during cold weather.

 

Tire pressure -> I would go to the max psi on the sidewalls for the front and 2 less for the back. Heater at 70F is high. You have heated seats use those to offset heater output somewhat and I would leave you heater on 65-67 (I see a real mpg hit when the heater is over 67 - I think it is that the ICE doesn't stop much when at stop lights etc when the heater is over the 67/68F or so). Scraping the windshield is tough but I used to put a piece of cardboard on mine each when I lived in Canada and that worked like a charm.

 

You could just 'upgrade' to a more impatient class of friends.

 

I agree with our first statement. I am new also but am getting in the mid 50's not driving any particular way more on that below. Is P&G a Gen. 2 driving method, does the theory/practice work with a Gen. 3?

As stated above I don't know much about P&G. But I am a Big Fan of ECO mode, even though you still have to slide over in to PWR now and then. Tire Pressures 40 PSI all the way around.

Changed oil at for first time at 1073, engine sounds better and not as rough now with Mobil 1 0W-20.

I tried to post a reply to this thread last night before bed but I was closing multiple windows and closed the thread and all my work was gone.

Here we go again... I have had my 2011 V for 3.5 weeks now and as of this morning I have 1792 miles on the ODO. I have am on my fourth tank of fuel I have filled it up three times it came full from the dealer. Here are my stats.

View attachment Prius Fuel Log.pdf

Currently, ODO 1792, TripA 325.1, Cons. 56.6, Avg. Spd. 29, DTE 201

I commute 25 miles to work one way, it is mixed driving rural under 35 MPH, Highway, and some stop and go. The last 8 or so miles is uphill I try not to go over 65 while climbing and like I said I use the DRCC when I can. I drive conservatively now compared to my former car but not I don't really try hard to get my MPG's. I do not have winter to contend with over here either, if I did I would probably also have a MPG drop. As stated above I keep the car in ECO mode always, even though it is necessary at times I try not to push the sliding scale on the HSI in to the PWR area but sometimes you have to. I do release the brakes and then coast out of a light rolling out then slowly accelerate trying to hit 15 MPH before crossing the middle of the sliding scale and kicking on the ICE. When I do cross the middle of the sliding scale I continue to accelerate smoothly to my desired speed and then retard the accelerator pedal to allow the CVT to adjust to a more favorable RPM and then get back in to the pedal to keep speed while watching the instantaneous MPG indicator to try and stay above 50 MPG and still keep speed. I also try to leave a good gap for braking and accelerating as best I can I usually get cut off by people pulling in front of me and then braking though. I don't know if what I am doing is similar to P&G or not?

Lastly about the tires it is not cold here but I raised my tire pressures and have not noticed a MPG increase. About two weeks after having the the car I checked the tire pressures they were LF 36, LR 36, RF 37, RR 35 PSI respectfully. I raised them all to 40 PSI all the way around just before my last fueling the ride got harsher but no noticeable MPG increase. I am probably going to leave it at 40 PSI, or maybe drop all 4 down to 36 PSI to smooth it out a little.I think the recommended 33 PSI front and 32 PSI rear is to low. Remember Dweezil and myself have the P215/45R17 tires.

 

Besides the tire pressure and the idling to deice......

Try NOT to be near the middle line, it is actually inefficient to be there. Hobbit had an article on this

HSI

He outlines the "sweet spots". Happy reading.

*Edit* For my 58+ mpg, I've got a 35 mile commute, which is 80% highway with some slow and go (slow and go = pulse and glide...about 3 miles worth each direction). Mild Bay area climate helps a lot as does the fact that I try to keep my freeway speeds around 60 mph). There is an elevation change (about 400 - 500 feet) that I go through daily. The weekends typically kill my tank mileage as my trips shorten dramatically.

 

Cool thanks for the link, thats good info. I do not drive in the middle, but I do not understand the P&G method nor have I researched it yet either. I may be doing it and not even know it. I was just stating that to the left of center will be EV and then to the right side the ICE will come on. When I am leaving a stop I will try and stay to the left side of the scale until 15 MPH, then continue to accelerate smoothly to my desired speed. Then release the pedal and reapply accordingly, like mentioned on the Hobbit's page and the owners manual.

 

Dweezil, I found it takes less work to get a Gen3 to the Gen2's numbers.

First, read your tire's sidewalls & inflate to max sidewall pressure.

Second, subfreezing temps are killers. If I got minus mpg in the morning I wouldn't be surprised. The electric seats don't seem to zap FE but unless coolant temp is 150F running the heater will run the ICE just to try & keep everything warm. I've seen coolant temp drop 10F just sitting at a traffic light. I set the climate control to 70 & auto. Block your grill.

Third, can you change your route to take advantage of slower roads or cut the speed back on your current route?

Fourth, buy a ScanGauge so you can see what is happening.

 

Here is a really good video that might help as well:

 

cool video. something I always wondered, when doing the P&G why do you release the accelerator pedal fully then apply a slight pressure to it? how does this differ from just slightly lifting pressure from the accelerator pedal?

 

I think it's the cold weather. I went from avg 50 mpg to avg 40 mpg when it touned cold here in indiana. The colder it gets the worse the mileage.. I hate cold weather. How about you Prius drivers in the warm climates, does your mileage remain steady year round ?

 

Remember, going back in time wrecks the MPGs, as well.

Best advice I've seen yet: make sure your tires are pumped up, stop letting it idle (the glass scraper is your friend), and just drive it. No more trying to run on battery.

 

I have seen a difference in 10 mpg in one day. Morning temps were in the low 60's. Drove about 75 miles to Longview WA.

While there a cold front with rain came in and temps dropped into the 40's.

On the way back we dropped at least 10 mpg. Everything was equal and that is what cold weather, rain, will do.

Our Prius loves warm dry weather.

al

 

Lowest tank calculated was 44 MPG,
Highest tank calculated was 59.88 MPG
Average lifetime 54.6 mpg

13 mile daily commute.

for last 18 months