Real driving MPG?

How strong a conclusion do you think you can draw from one driver and two cars ?

Here's my anecdote: old EPA in my Honda Civic, 20% better than old EPA in my '04 Prius (about 70 mpg).

 

Many modern cars have mpg displays, so this is not unique to hybrids. My pre-hybrids didn't, but except for the HSI display, the Prius tells me less than the ScanGauge added to my older Subaru 13 months ago. Most of what I can learn from Prius's helpful tools was already incorporated into my driving style.

I started keeping close track of fuel economy in 1986, with the purchase of a new Accord. It beat its EPA highway rating right out of the box, in winter. When summer came, I averaged 20% over EPA. When the national 55 mph speed limit was repealed, I improved enough to get the same mpgs, despite higher speeds. And it continued to get good numbers right up until its retirement last month.

At first, my 1997 Subaru failed to get its EPA highway rating, but I did learn to reach that, in summer, long before the EPA downgraded its ratings system in 2008 to match my original results. Upon hearing about ScanGauge, I immediately bought it, and soon learned how to beat the old EPA number by 20%. (Hint: most of that improvement was available without any display whatsoever.)

With this history, I am slightly annoyed to get 'only' 55 mpg out of this Prius. But hey, it isn't really broken in yet, I haven't really learned how to drive hybrids, and our unseasonal heat has required far more AC use than normal. I'm expecting improvement over the coming year.

MPG is a strong function of driving style. If you live in an area where you must hammer the pedals and exceed speed limits to avoid getting run over, then EPA ratings may be fiction. My area isn't so aggressive, so the ratings are easily achieved by those who desire to do so.

 

I'm glad the Prius is living up to the MPG expectations of so many people.

However, it is not for me. If I drive like a grandpa it gets close to 50 mpg, if I drive like a regular person it gets 43 mpg. That is MY experience.

I still love the car though.

 

I suspect that your driving situation is considerably more aggressive (not you perhaps, so much as your area as was suggested before) when compared to the EPA testing protocol. In another car, where the mileage already sucks (and frankly, 21mpg sucks) and the engine is huge, the difference in driving style probably doesn't matter as much. In the Prius, with it's just-barely-big-enough drivetrain, going from the EPA test protocol to the aggressive style that is realistic for you would tend to make a much larger difference, I would guess.

And as pointed out, the percentage factor changes everything. Add in rounding, and the two are not so far apart. For example, what if the 21mpg rating was rounded down from 21.4 and your 20mpg actual was rounded up from 19.5. Then the actual difference is 1.9mpg or 9%. A 9% error against 49mpg produces a result of 44.5mpg... make that 44.4 and it would round down to 44mpg... not so far off your reported 43. I'm just saying...

For my personal experience, on only my first tank, I'm getting pretty much the EPA rating without really trying and including several stupid acceleration runs to prove to skeptical friends that it really can get out of it's own way. Again, in my personal experience, 'driving like grandpa' would yield way into the high 50's or maybe even 60mpg.

 

You lost me there... so I'm a grandpa now and not a regular person? I'll have to relay that to my wife and family who think I drive too fast. And I wonder if I could get a note from you that maybe I could use to get seniors' discounts at restaurants... The possibilities are endless.

 

Yeah, from my experience, to get mileage in the low 40's I'd have to accelerate full-out and brake just shy of ABS almost every time -- and maybe go everywhere at 85 on top of that. Even then, what car will get close to that mileage with that kind of usage?

On the other hand, given that I don't want to hold up traffic nor find back roads to P&G on, I find it a challenge to keep my overall mileage at 55 or above for a week. It's weird how strongly the car wants to get the EPA estimates.

Another factor in the OP's drive may be distance. If I could ignore warmups, I get WAY better mileage. For example, the other day I forgot to reset my Trip A (weekly mileage) until I was 10 minutes down the road and well-warmed-up. I had more highway miles than usual, and a longer drive, and by the time I ended the day, I had 60 MPG.

I've fought to maintain that, but it's been sinking the rest of the week, down to about 54 right now.

From what I've seen, while the car is warming up you'll get around 35 MPG. So combine a lot of warmup time with a teenage boy driving style, and I can imagine you get around 40 MPG.

 

Haha. So sensitive wfolta... stop personalizing everything. I said that "I" would have to drive like a grandpa to get into the 50's. I am speaking about MY experience, if you have a different experience, good for you. Believe it or not I am not an aggressive driver either, and I have always employed gradual braking because I want to save my pads.

Are there any other Los Angeles drivers here that would like to weigh in on their MPG? I am curious to see if they are averaging as high as everyone else seems to be. Maybe it has to do with my route to work everyday which is a combo of city and highway traffic.

 

Ok, I'm really confused . I grew up in the L.A. area (and learned to drive the L.A. Style). When the traffic light was green, firmly step on the right (gas) pedal. When the traffic light was red, firmly step on the left (brake) pedal.

If I would "gently" step on the left pedal (brake), I found that I'd made lots of close friends. They would drive up real close to my rear bumper, sound their horn, and give me a friendly California wave (usually with one finger), and speak loudly in a foreign language (which my father told me was a dialect of English used primarily while behind the wheel.)

Keith :focus:

 

I would have to get out and push to get more than 50 miles per gallon. I do drive with the air on and fans turned up. Since new, I'm just a hair under 50 MPG.

I drove one of my sports cars the other day and could not get use to the idea of having my engine running all the time.

 

[QUOTE If I would "gently" step on the left pedal (brake), I found that I'd made lots of close friends. They would drive up real close to my rear bumper, sound their horn, and give me a friendly California wave (usually with one finger)[/QUOTE]

It's true that it's difficult out here, but I find that if you can keep the A-holes behind/ or to the side of you, it works out ok.

I'm still on my 2nd tank, I will check back in on my 5th or 6th and let everyone know my average.

 

ok, my most recent tank, another huge discrepancy between the MFD and pump readings
(61 to 53).

now this tank was different because we are now ending the greatest heatwave in history of the Pacific Northwest... AC was used extensively. a few times, when i would have left car running with nothing on, or even had turned car off, had to leave it going with AC blasting cause son was in car. (now before you report me to child services, i was never beyond sight of the car) one time it sat for a good 15 minutes (was at Costco filling two cars at once...pump went out of service causing car #2 to have to get into another line.

but i think i short-filled the previous tank causing the larger difference here

 

I got my 2010 Prius last Saturday and was pretty disappointed during the week to find I was getting slightly over 40 MPG all week. Many folks here were bragging about mileage in the 50s and I wondered what I was doing wrong.

Well, here is what I've learned. First of all, I live less than a mile from work. So the car barely had a chance to heat before I was shutting it off. Second, it is August and I live in Florida, so the A/C was blasting to try to cool the interior down.

Now the good news. Today we had our first chance to really take it out for a good spin. We drove it up to Tarpon Springs and back, a good 50 mile hike round trip. I drove up there, and my wife drove back. We watched the readouts and tried to drive in a reasonable manner, but I can't really say we were driving any differently than we've driven our other cars.

On the round trip, we averaged 52 MPG. So there's nothing wrong with my Prius. It just doesn't like a lot of very small trips. Once the ICE heats up, and the A/C cools down the interior, that little bugger kicks nice person!

 

Yeah, short trips will kill your mileage. I still average 50-55 on a weekly basis with a commute that's 11 miles each way -- average about 30 miles a day by the time you add in various trips during the week. But I've started tracking individual trips and as an example, just drove on a short 5-mile trip and got 40 MPG. (It's .2 miles from our parking space up to the garage doors, which starts me out with a horrible 15 MPG.)

 

I've noticed an interesting thing in following other threads, including this one:

http://priuschat.com/forums/gen-iii...0-tire-pressure-mpg-tests-tire-inflation.html

What I've seen is that there seems to be some significant variation in the pressure dealers are setting the tires on delivery. Some seem to be setting 32/30, while others are setting as high as 40/40 (how mine was on delivery). That much variation in pressure will make for a real difference in mileage and I'm wondering if the different experiences expressed here might be explained, at least in part, by different settings of tire pressures?

 

I think the 40/40 was how they left the factory, and the dealer didn't set them back to 35/33 that's on the door placard. I've read on other boards that the manufacturers put more air in to prevent flat-spotting during the boat ride over. Mine were delivered 40/40, and I bumped it to 42/40. Just checked them today after 5 weeks, and they'd dropped to 40/38. Bumped them back to 42/40.

I was surprised that they'd dropped 2 psi to, since the weather's generally hotter here than it was 5 weeks ago.

 

Man, I must drive like an a$$ because I have been averaging between 40-45mpg tops. I left the car on cruise at 75mph and I still can't get more than 45mpg

 

You need an engine block heater. Or a bike for your commute.

Wayne

 

Perfectly agree with you about the bike. However, is an EBH worth the extra electricity? Isn't it a negative sum game?

 

No car likes a lot of short trips. And yes, the A/C hit is even larger for small rides since it goes on full blast to cool the interior. After the interior has reached the desired temp, it will throttle down. I usually leave the windows open and A/C off for rides in town (<60 kph).

 

Mine were 40/40, which I'd assumed was part of a good-cop/bad-cop kind of deal: the salesman direly warns you to not exceed the Toyota values or you'll wear your tires out prematurely, while the mechanics go 40/40 (should be 40/38, but) so you get better mileage right off the batt and when you finally check it you decide to keep it higher. But, of course, Toyota's officially given you the warning, in case of lawsuits.