37 MPG !?!?!

http://priuschat.com/forums/kb.php?mode=article&k=23 is a good article to read. You're helping with the tires and the driving habits, but it's more than that. I know someone who was getting 39mpg, largely due to his commute.

 

You are going through what just \about everyone else has. The gas mileage you are experiencing is not all that uncommon - especially in in winter. Between the winter formulation of the gasoline as well as having your heater and defroster on and thereby keeping the ICE running more is nlt helping. Take it easy and enjoy your new car and learn all the features and wait until the break-in period is up. I remember a nice jump when my car reached 4500 miles. What speed are you driving on the freeway? Pedal to the metal is gonna eat up your gas.

 

If you're getting 25 MPG in city driving something is not right unless you're doing 1 mile trips in cold weather. How would you characterize your driving style? Just what have the temps been. From the looks of it you're driving a lot during a typical week so I'm assuming that you do a lot of highway driving. Is that correct? What's the terrain like in your area? It's probably NOT the car itself. The likely souce of the low mileage is either your driving patterns (ie lots of short trips) or your driving style (lead foot/aggressive) in combination with environmental conditions. Also, factor in winter fuel and a new car and that'll ding you somewhat. Look at a lot of the "old timers" fuel economy graphs (see TonyPSchaefer and EFusco's signatures) and you'll see that they're mileage improved each year as they learned the car. Summer fuel, warmer temps, and a broken in engine will help your cause even if nothing else changes.

 

Can you describe your transit for a typical day during the last week? Mostly, how many trips per day, how long were the trips, and what kind of speeds were travelled.

 

what is the speed when you are doing the highway driving ?
Try to keep it around 65MPH

Let the car break in a little before thinking you have a problem.
At least 5000 miles would be good.
Cold weather is very hard on the MPG
Also try using the cruse control for highway driving.


more than likely the problem isn't the car.... it's the driver.

 

If the temperature outside is well below freezing and you have the heat on most of the time, 40 MPG per tank is typical. I had a 39 MPG tank earlier this year, although I'm back above 50 now.

 

Just try to relax and remember that you are probably getting at least twice the mpg you did on your last car - or your boss gets. It helps to put it into perspective.

Frankly, the extra weight from the the passengers contributes. Can you leave them home?

 

I've seen as low as 33 MPG for a tank this year, and I've got close to 10,000 miles on my '05. Winter is a killer, as are short trips. Running the heater keeps the engine running, so there goes more gas.

Until it warms up, you're unlikely to see the full potential of the car. Try to coast as much as you can approaching stop signs/lights. I also accelerate very gradually to try to maximize the time the ICE is not running.

 

a lot of it is the fact that it's in the 20s and 30s out near you. that knocks down the mpg on any car. but couple that to having a new car, with tires that aren't yet broken in, and a driver who's still learning the nuances of high mileage driving... and you get upper 30s mpg.

i got my prius a year ago today. it was cold, rainy, gloomy, and generally nasty for the first couple of weeks. my first tank didn't break 40 either.

it's not the car. relax about that. just take some time, a couple deep breaths, and be patient. the weather will warm up, and you will pick up the subconscious prius driving instinct

 

Don't use 89 octane. It's not good for the emissions system and won't help you out in anyway. It just costs more.

 

Check your oil level. if its much higher then the full mark.. that could lower your MPG by about 5mpg.

It could be that the first tank you got had bad gas... it happens... and then you filled up with 89 when it wasn't completely empty and you still have some bad gas.

at 30-37 degrees you should get 42-45mpg. Also depends how hilly your commute is....

P.S i don't think 89 will give higher MPG would it ? the engine is designed for 87.

 

I expect you have two major contributers, temperature and length of trip. These cars allways get very poor milage for the first five minutes or so, then marginal milage for the next five. With a trip as short as yours, the time after the warm-up isn't long enough to overwhelm the eairlier milage. This is heavilly compounded by the cold. The ICE dosn't run very warm, so even a little bit of cold makes it have to work harder to get its temperature up, thus burning extra gas. If you run the heater, it gets even worse. (And at freezing temps, not running the heater is nearly unthinkable.) I have watch my engine reach about 180F (where it usually runs) then drop to 140F almost immediatly on turning on the heat. It won't make it back to 180F for 7 or 8 miles. And this is at temps around 60F outside. My be would be that as you get make to your non-slow driving weeks, you will see an improvement. It will be even better when the weather warms. Or, just move dowm to Phoenix and get 48mpg during the winter!

 

I got around 40MPG in Michigan for short 3 miles commute in the past two months.
Recently, I got 44MPG because temperature rising a little bit.

 

I can drive mine and get 16mpg (lead foot) or what I normally do is do the ev takeoffs and cruis down the road..

Are you driving up hills? I drove to texas and averaged 50mpg (90* weather) on the way back had to change course due to Katrina, driving through the rain bands was a bitch.. I only avaraged 32mpg but when I hit the evacuation traffic jams it would go to 100mpg as I would only use the ev..
Man what a trip drove 23hrs the same path/evacuation route of the storm but thats another story...
I guess my point is driving habits/conditions/geogerphy can play key rolls in mpg's..

 

The first 1500 miles I averaged about 43 MPG. It is still cold in PA and I drive 10 miles each way to work so the car barely has time to warm up. The one trip I did that was 130 miles ( 3 hours) I jumped to 54 MPG. As soon as we had a few warm days in a row my 10 mile commute jumped up to 51 MPG.

My guess is that given your location it is probably the cold weather that is keeping your MPG lower than expected. As soon as we get temperatures consistantly at 55 and above you should see a big improvement.

Springtime

 

Another way to increase your MPG's in the winter is install a block heater. set it on a timer to turn on and heat the engine 3 hours before you leave for work. The cost for the electric is very low and as the price of gas goes up it may pay to do that.
Maybe others could report what the MPG increase would be.




Good luck and enjoy !

 

Hi Efrench,

I have been drivng my new 06 Prius since early Febuary in Chicagoland here. My experience is that the car does not even start to increase in the tank average indicated mileage till 1/3 to 1/2 the way through my 25 mile commute. Your problem there is that your commute is too short for the average to start increasing.

The warm spell we had here last week helped a bunch. That battery seems to perk up some with the warm weather, and there is a very noticeable difference between days that are overcast and sunny but the same temp. Last refill was at 48.2 mpg indicated, 53.5 Miles/gas pump gallons (probably just a cold rubber tank that did not expand all the way) - 440 miles.

Not having allot of traffic on the highway may be detrimental to your mileage. On a sunny above average warm day, with an accident about 30 miles down the road, traffic was pulsing and gliding at 25 to 45 and the Prius was loving it. For 5 miles, and 10 minutes I had a 100 MPG average - could not believe it. A steady 70 MPH would have resulted in 40 ish MPG.

Having slow traffic in front of you may be detrimetal to your mileage. Snowed recently and got behind a joker doing 20 mph while the rest of traffic was doing 40. We never caught up with traffic, and could not get out from behind him! Could not stay in electric glide at all. Same section of road , just a little bit colder (32 versus 35) - 40 mpg average! Electric glide (warp stealth) requires at least 35 mph in cold weather. I read somwere that tire rolling resistance is a k/speed function, and decreases with speed. Might have something to do with it, might be running faster heats the tires up and reduces rubber slap losses. Whatever 35 mph is a must to be able to drop into electric glide when the weather is below 40 F! The poor mileage at 20 mph might also be the engine running all the time in the zone where its efficiency falls off too.

Advice - Do check the oil level and I read you have already checked tire pressures. Temperature control - I have my winter coat on anyway, so I set it to 67 F. The difference between 67 and 70 seems to run the fan at high speed for about twice as long. Are you running automatic temp control? Took me a while to figure that climate control out. How is the defrosting situation there? Defrost seems to force the engine to stay on. Get out of defrost fast, and turn the recirculation on and off to keep the windows clear. This only works if the outside air is dry. Sometimes its better once defrosted to up the temp a little bit (70F) to help with window defrosting - and thus avoid turning the defroster back on. Defrosting may be problematic with your passenger moisture however, and especially if their coats have snow on them when they enter the car. Knock the snow off your boots before getting in the car - 1/2 inch of snow on the soles of your boots will melt and evaporate - the heats of melting and vaporisation of water are huge - and that energy comes from the car's gas. Keep the car doors closed when stopped and waiting to pick up. Hopefully your passengers enter and do not leave the doors open while waiting for other passengers or something else to happen. Are you or they smoking and have a window cracked for ventilation? Coffee drinks should be capped to avoid the moisture escaping. Park with the front of the car pointed at the sun in an area where the afternoon sun will hit the car. This helps keep the battery warm for the drive home.

Dropping into electric glide works best on a slight down slope and with no traffic in front of you. Get up to about 35 or 40, lift throttle ALL the way for 2 or more seconds of regeneration (green) arrows - this is when the engine turns off, but you may not even sense this. Then slowly increase accelerator until only the electric drive arrows come back on. Maintain that accelerator position. The warmer it is the more of a range of increasing the accelerator you will have before the engine pops on. Also the warmer it is the better acceleration you will get but generally, one can maintain or increase speed only a few MPH in this mode (without an electric mode switch - I guess). Once in electric glide for some seconds, the car is more forgiving of throttle movement before it pops the engine on. If traffic starts to pull away, I accelerate with the engine till a little bit faster than traffic, and repeat the electric glide entry proceedure.

I find that I can use electric glide after leaving the highway for the 3 miles to my destination both on my way to work and on the way home. I regularily get 75 MPG 5 minute bars for this portion of the commute. Lately, with traffic acting up I have been using electric glide on the highway too. How successful one is with it depends allot on the circumstances of the traffic - and paying attention to the MFD in "ENERGY" mode. That might be a problem with other people on-board, while not having driven the car long enough to get a intuitive feel when you can drop into the electric glide subconciously - I have found myself doing that too when the MFD is in "Consumption" display. Then again, maybe you can get the shot-gun seat guy to read out the modes while you keep an eye on traffic. Kinda like an ecnonomy road rally team.


Hope these comments help !