Fuel mileage in the toilet now that winter is here

But like others have posted before. If you get 48 MPG in summer and 40 MPG in the winter if you used 10 gallons of each tank then that is 80 miles less and only 2 gallons more per tank. With gas around $3.00 a gallon. That is only $6.00 more a tank. Not bad compaired to regular cars. Yes some may be a lot less but it is only a small amount in the big picture of it. My old tundra truck got 15 mpg. My hyunda sonata got 29 mpg. My prius gets 45 to 50 mostly highway. I have driven 10,000 mile since I bought my prius in July 2013. So the same miles in each vehicle would look like this.
Lets say gas is $3.00 a gallon.
10,000 miles
Tundra truck 667 gallons of gas $2,001
Sonata 345 Gallons of gas $1,035
Prius (average 45 mpg) 223 Gallons of gas $669

 

Get the block heater? Dealer installed is pricey, in my experience. But it'll help. Not miraculous, but it'll raise your coolant temp to around 30~35 Celsius at start up.

 

Also a lot of people go more places in the summer like long road trips and other summer fun stuff. Winter is for only getting out and going to work. So hopfully less miles in winter. Combine trips to save on trips.

 

I have 10,000 miles on my prius in just 4 months and only about 4,400 of that is for work and running around town. But this summer we went on road trips for concerts and other things that added 5,600 mile more on car. I will not be doing that in the winter time.

 

What about getting a remote start for the car to help it warm up vefore you drive. Would this be something to help? Ive noticed a slight drop already in my MPG as well and trying to think of ways to fix it.

 

Remote start defeats the purpose of getting better mpg's. The ICE will warm just as fast when driving it versus remote start, and you're putting miles on it at the same time. It shouldn't take more than a mile or two before you start getting heat. Grill block will help. I grill blocked my previous 2010 liftback anytime temps consistently were below 60.

 

Is there any threads here to help grill block a 2013 prius. I am not that good with cars so I need to know the basics lol

 

Definitely seeing a decrease in mileage on my PiP as the ICE is much more sensitive to firing in cold weather.

That said, I do have some good news to report - did a 225 mile drive this week at 30F, Michelin X-ice3 tires. Got 53mpg generally doing 70+. Not bad!

 

Go to Home Depot or Lowes and buy the foam pipe insulation - I believe it comes in 6' lengths. Cut to size to fit in the lower grill slots. Generally, don't block the upper grill unless you experience some ultra cold temps. There are several threads that talk about doing it on PC - search for 'grill block' and you should find them.

 

Just sharing some recent observations based upon miniVCI recording of warm-up:

• The engine is just terribly inefficient for the first 1-2 minutes with an excessively rich mixture. This is used to prevent engine stalling under load when cold.
• Acceleration when the engine is still in "open loop", cold, means the least efficient, mixture. You will reach some speed but you'll burn a lot more gas because of this excessively rich mixture.
• Waiting just one minute is typically all it takes for the idling, minimum load, engine to begin "closed loop". For a cold, snow or ice covered car, a great time to scrape the windows and clean the mirrors.
• When the coolant reaches 40C and the heater is off, the car will stop the engine at a stop.
• When the coolant reaches 55C and the heater is on, the car will stop the engine at a stop.

Now if I lived on the top of a shallow hill so I could roll down for about a minute, I would agree. Take the hill and get some miles. But if I lived at the bottom of a hill or a flat section, I would (and do) let the engine run in "P" for the first minute. You can actually hear the engine tone change when it transitions from "cold start" to "closed-loop", the self-tuning mode.

GOOD LUCK!
Bob Wilson

 

I agree if you're doing any kind of moderate accelerating on a cold ICE your mpg's are in the toilet. I typically creep down the driveway to the street, then up to the stop sign. It's about .8 miles to the gate to exit the community, and many times my ICE will shut off then while waiting for the gate to open if I don't have the heater on.

I assume some people would use remote start to get the interior fully warmed up before leaving, and others will use it to let the ICE run a few minutes before drive off. In either case, I think it's a waste of gas. If using it as you say to scrape ice or snow off the car, then it's worth it. But given a convenience, people tend to overuse it because of its novelty, not realizing it wasteful. I remember growing up in CO, my dad would go out and start his truck 20 min before he left for work some mornings - what a waste!

 

I think it's actually illegal in our area, excessive idling. Not that it deters anyone...

 

So far this year my results with the colder weather have been pretty good. I am averaging around 52 mpg with a "flat" lower grill block rather than using the pipe insulation block. It is retaining heat well and improves the air flow on the highway.

 

Yup:


Idling is getting official discouragement around here too, though no actual prohibition yet.

 

Illegal excessive idling, lol. You got to be kidding...........

 

He isn't kidding, see the pic I posted above. And the concept is spreading.

 

The energy absorption and dissipation efficiency of your pack (how fast it charges/discharges) plummets drastically at 0C (32F).

I'm guessing you are doing lots of short trips in the city??

Its annoying, but there is nothing you can do for you short trips/city driving. You will see better MPG's in longer trips tho.

Don't worry, it's just thermodynamics hampering your ride, It will go away in spring or longer trips!

 

Priuses use a heater core to exchange energy already made via engine combustion to the cabin. I assume that the energy impact you experience was do to low battery temps. The heater core passively heats the engine (does not use a heater wire). Fans however do create a high energy impact, not as high as AC tho.

 

You can use the heater while you're driving and the ICE is running. It's not the electric load killing your mileage, it's the loss of heat while the ICE is not running that forces it to run more often in cold temps, especially at stop lights. Just turn it off when at a stop and turn on when you're moving down the road with the ICE running. It's a pain to do it all the time, but it sure helps your mileage and you don't have to suffer without heat.