Driving for Economy Tips, Please!!!

[Brian]

I received my Prius on Monday. I am not getting the best mpg right now. It is currently at 37.6. I only have 95 miles on the car and the second fuel level indicator light is out. I just need some tips on how to get the mpg up there in the high 40's. I need some help here.
Thanks,
Brian

[xlarimer]

just wait...

It will change...it almost feels alive and moves around depending on temperature, elevation, driving style, etc.

Also, I've noted that somtimes when i fill up the tank and take the mileage by hand I'm getting more than what the computer says, sometimes it is less. I think it has to do more with how I fill it up.

I was worried at first, but it will go away soon. Besides, 37.6 is still better than many cars out on the road AND you are releasing much less emissions than many other cars out there as well.

[Brian]

Thanks xlarimer, I guess your right. Thanks for the enlightenment. I am not going to be worried anymore. I have a question, when it gets warmed up, I am VERY easily able to keep it in stealth up to about 40 mph and able to substain this for a while. Is it a good thing to do that, with respect to fuel economy?
Thanks,
Brian

[Bill60546]

Brian:
When I first rented a Prius for two weeks while my Honda was being repaired, I found using the cruise control, even in city traffic, made huge improvements in MPG. The accelerator, which is electronic, not mechanical, is very sensitive. It helped improve my driving patterns, etc. I went from 35-37 to 50-52 MPG almost overnight.

[Astroprius]

Brian -

Here are a couple of suggestions for getting the most economy:

1) Use moderate accelaration to get up to speed and then back off the pedal. Sometimes you have to completely remove pressure from the pedal and then resume light pressure to maintain speed. This is usually how you can get in to stealth once you are at speed.

2) Anticipate stops and, if possible, slowly brake for as long as you can. Sometimes traffic won't allow for this (especially if you have someone on your rear)

3) Combine your trips so you are driving at least 10 or so miles at a time. Short trips will reduce your economy, especially in colder weather.

4) Tire pressure at 42 front, 40 rear. This is recommended by many of the "experts" in the Prius community.

Hope this helps. It seems to work for me (current tank has 634 miles, averaging 60.0 MPG in combination city/highway driving).

[rflagg]

Re the accel. being touchy, and cruise -

I wholeheartedly agree. When you have a chance when your driving conditions are near ideal (ie, a chance to glance down at the screen without worry of other traffic), take a mental note of what your 'current' mpg is, then lightly let back on the accel (or push forward) just ever so slightly - the accel. will barely move, and you should notice that even with the ICE on, your mileage might jump from mid 30s to mid 50s or higher.

When I accel. from a stop (light or sign), as long as traffic is cooperating, I try keeping it in stealth til about 12mph, then the engine will usually kick in. When it does, give it a bit of a punch, and try to get up to 'cruising' speed as fast as possible - while this will push the ICE harder, it will push it for less time, giving you better mileage overall.

And no matter what you do, if your trips are short, as mentioned above and elsewhere, your mileage will be lower than anyone who drives for long distances/times. Truly you'll find this car can easily make you a better and more aware driver, even if you knew nothing about cars beforehand.

-m.

[efusco]

I probably need to put this in the FAQs as it's asked so often, but let me list some of the big things to do to improve your mileage:

1)Be patient. There is a signficant break in period for the car (engine, bearings, perhaps even some computer 'learning'). Also, there is a break in period for the driver. You have to get used to the feel of the engine, when it's over reving, under reving, etc. Your anticipatory driving and braking skills will improve.

2)If you are enjoying relatively moderate climates turn your AC to OFF. To keep a 'vent' on do the following. Push the Climate button on the MFD (multi-function display (the monitor)), if the AC button is lit, turn it off. Now push down on the temp setting until you hit MAX COLD. If the AC turns back on, turn it off again. Now, you can touch one of the fan speed buttons..I rarely need anything stronger than the second or third button from the left unless the car is really warm from sitting in the sun. I saw an almost 4mpg immediate improvement in gas mileage by not leaving the AC on all the time. Of course, if it's really hot or really cold and you need to use the AC, then, by all means, do so. Also, avoid the defrost buttons as much as possible, they really chew up power.

3)Consider adjusting your tire pressure to something in the range of 40F/38R (I use 42F/40R, others go as high as 44F/42R). I find that it improves handling and there is some evidence to suggest improved mileage and longer tire wear. This is a bit controversial (see the current thread), but it works for me and many others.

4)Drive casually--Look ahead, is the light likely to change to red before you get to it? If so, start coasting or breaking as soon as you see that. Your ICE will shut off sooner, you'll begin regenerative braking sooner, you'll reduce hard braking which can wear your friction brakes faster. Don't gun-it to pass people, don't drive in the fast lane. Try to avoid situations where you need to accelerate quickly for lane changes.

5)If where you live is relatively flat or you have extended areas that are pretty flat, use the Cruise Control. It helps avoid fluctuations in speed that can use more fuel. If you're in a hilly area it can be much better to AVOID CC--don't try to maintain speed over hill crests, just coast over them and let gravity assist you to regain speed on the downhill. Now, don't take this advice to any extreme, but often I find that as I'm approaching the crest of a hill, the ICE will have to really rev up to maintain 45mph, whereas if I take my foot off and 'feather' (see below) the accelerator I can hear the ICE actually shut off, and I can still maintain up to about 42-43 MPH, hardly any drop at all and I used no gas. I can then, often, pick up speed again on the downhill side while still coasting. This takes practice and a bit of a learned touch to avoid pissing off everyone behind you, but in the right situation and with practice becomes very natural.

6)Achieving Stealth is not, necessarily, a good thing. It is less efficient to use the battery, in most cases than the ICE assuming all the power from the ICE is being used for accelerating/powering the wheels. There is some loss of energy inherent in the transfer from ICE to batt. to wheels. That said, at times where the ICE would otherwise be running inefficiently (low RPM, excess energy going to the battery) then Stealth may be the best situation.

7)Another situation is coasting. If you take your foot totally off the gas while watching the energy screen you'll notice some regeneration going on and slowing of the car. That's fine if you want to coast to a stop over a distance, but one can also learn to 'feather' the pedal to coast. Let your foot totally off the pedal briefly, then very gently touch it back down until you see all arrows disappear on the Energy screen. You'll notice that you do not slow nearly as fast as with the foot totally off, you're using no energy and the only thing slowing you is internal friction in the car and the air friction acting on your 0.26Cd car. You can coast a good long way with very little loss of speed. This is another good plan when you have a long way to a light that you know you may need to stop at but don't want to start braking yet.

8)Switching to synthetic oil may gain you a tiny improvement--most likely not enough to justify the cost of the oil over mineral oil. There is a tiny added environmental benefit to synthetic. There may be some improved engine life if you plan to drive your Prius for 350k miles plus. I use it, more or less b/c of the environmental thing and b/c it seems like the most technologically advanced product for my most technologically advanced car.

That's about all I can think of at the moment. Be patient, drive casually, await warmer weather.

[Brian]

Ok, Will take all of those things into advantage over the weekend and hopefully I can see some improvements.
Thanks
Brian

[Brian]

I inflated the tires to 42/40 psi (it was set at 35/33 before) and went to the grocery store, only a short ~5 miles away and when I got home, my mpg were up 1.7 mpg. I think that with more practice and the tires up to 42/40 it will definitly improve. Thanks
Brian

[rockluvr]

Evan,
I think you should definitely put that reply in the knowledge base or faq.