Help me achieve the 51 city that Toyota advertises

The EPA cycle is NOT even close to Houston standards of driving.

You pretty much answer your own question with all your qualifiers and examples.

 

It is not a Toyota number, it is an EPA number. The EPA city test does not involve a cold start, the engine is already warm and the Battery is charged up. It mimics a very slow drive in a section of downtown LA in the 1970's.

Assumptions about what Toyota might so are not relevant, all they can do is follow the precise EPA rules. In the US, you MUST show EPA numbers in a larger font than any other mileage numbers you may wish to show.

 

CITY means NOT HIGHWAY.

It really is that simple.

SUBURB should be a seperate category. In fact, there is a third in the UK to clarify the very situation you've been struggling with. Unfortunately, our EPA here leaves the opportunity for that particular misunderstanding wide open still.

The "city" you are thinking is the least efficient type of driving... even for a plug-in. All that accelerating from a stop is quite wasteful.

 

your assumptions are all wrong

Please read http://priuschat.com/forums/other-c...uth-about-epa-city-highway-mpg-estimates.html.

The test was devised by the EPA, not Toyota. Throw out your assumptions about Toyota's numbers. The test results listed on http://www.fueleconomy.gov/feg/sbs.htm and the Monroney (window) sticker likely were conducted and self-reported by the automaker itself, but all according to the EPA test procedure. The EPA does test some cars themselves to verify those results. I'd imagine that given the Prius' high ratings, the EPA re-tested it.

Hints: The EPA test is conducted on a dyno, not a real road. The only tests started w/a cold engine are 31.2 minutes long. The city drive cycle is 11 miles long (and starts from a cold engine). AC is turned off on all but one cycle. The EPA test doesn't even measure actual fuel usage, but rather tailpipe emissions. The highest average speed of ANY of the test cycles is 48.4 mph.

Please read the above URL for more details.

As for Toyota and "expecting" the average driver to achieve such a number. There is no expectation. Supposedly, all automakers are legally required report and advertise to the only (?) the EPA numbers, although I've seen VW try to skirt the system before in some ads for their diesels (http://priuschat.com/forums/other-c...di-ad-advertising-non-epa-method-mileage.html).

 

Thanks- the engine is already warm. That makes a big difference.

 

As John stated above, stop and go driving is very wasteful. It takes a lot of energy to move a Prius. Because rolling resistance plays a large part in fuel efficiency at low speed, those heavy 17" wheels will hurt mpg much more in stop and go driving than at sustained highway speeds.

I also find it difficult to achieve great city mpg unless the route allows me to glide between stop signs/lights. In some areas this is easy to achieve and in others it is not possible. This is why EPA always states "your mileage may vary". They simply cannot reproduce every driving condition, scenario or vehicle trim level. Keep in mind that the EPA rating was set for the Prius with 15" wheels, not 17s.

I would suggest you try to accelerate a little more briskly. Get up to your desired speed the lift off the throttle completely. Gently reapply just enough pressure to maintain your desired speed. Then anticipate your next stop and start gliding as soon as possible.

Accelerating briskly is more like normal driving and less like hypermiling so driving should be more enjoyable.

 

I just noticed you are using the AC on those short trips too. That is a recipe for low mpg if you have the AC blasting and have many stops on your route. I would start paying attention to how often your engine shuts down at a stop with the AC on. Then try turning the AC off and driving with the windows down and see if the engine shuts down more often. The engine will usually run more often when the AC is on and running hard. This will definitely drop mpg in a hybrid.

 

The very first time I experienced Texas city traffic was hours after witnessing an icy spinout just barely in front of my own car in Spokane. My first thought: These Dallas drivers would be in extreme trouble in any sort of snow or icing conditions.

The next day, one of my interviewers was a Minnesota native. He confirmed my feelings with his story of his first Texas snow day. He noticed that the roads were nearly empty of cars, the ditches were not empty of cars, but only after reaching work and finding the doors locked did he think to turn on the radio. Only then did he discovered that the city had shut down.

Driving styles display drastic regional variations. Watching traffic behavior the few times I've visited, I'm not the least bit surprised that common Texans have difficulty achieving EPA numbers, even when it is cool enough to turn off the AC.

 

ethanol-free gasoline for better mpg

Many places offer gas saving tips. One tip not mentioned often, is NOT to use 10% ethanol blend gasoline, but only 100% ethanol-free gasoline. Go to pure-gas.org for addresses & a great zoomable map showing the minority of 5150 stations selling 100% ethanol-free gasoline. However, most large cities have severe restrictions by the EPA for selling 100% ethanol-free gasoline AND Houston is one of the worst. From the map at pure-gas.org showing stations selling 100% pure gas, Houston(& other cities) has a big region around them selling no 100% ethanol-free gasoline.
You might try local marinas, airports & farm co-ops(who may have 100% ethanol-free gas & have exemptions from the EPA) to see if you could buy their 100% ethanol-free gasoline, but that might be a tough row to hoe.

 

Like you I have the 17". I keep my tire pressure at 42/40 front/rear. My drives are usually at least 7.5miles or 20mins long to work. Where I live we have no freeways. I never take my car on highways so I rarely clock over 60mph. So my avg speed per tank is about 22mph. I accelerate with the HSI just into the PWR zone. I do try to pulse and glide whenever possible but not if someone is behind me. I rarely use A/C in summer and at current temps here, I don't even run the fan. I leave a crack in the window for air to circulate. Avg temp for past month is about 60F.

Under these conditions, I got 10 consecutive 50+ mpg tanks (calculated) from May-Nov of last year.

Short drives will kill your mpg. Even if you stop for 10min to pick up some groceries, you think it's warm, it's already cool. Running errands from groceries, Walmart, Indigo/Chapters, Home Depot, Starbucks......kills my mpgs every time.

 

Take a look at your window sticker. Under where it says "51" in big bold type is a bit of fine print. It says "Expected range for most drivers 42-60 mpg." It also says that "your mileage will vary depending on how you drive and maintain your vehicle"

I drive "normal" (no hypermiling) and average pretty much right at 50 mpg. I live in VA so my A/C is on a lot. If you are running the a/c a lot you might want to try running in eco mode, it cycles the compressor a bit less so it won't drain the battery as quick. Also as soon as I get in the car and turn it on I go. I don't wait until the engine "warms up" or the inside of the car cools off. This is just wasting gas because you are not turning it into forward momentum so your average mpg will drop.

Also I noticed my mpg really improve after about 1000 miles. I'm not sure if that was because of the car "breaking in" or from my driving style changing. Probably a bit of both I suspect.

 

Besides the stuff I pointed the OP to about the EPA tests, he should also look at CR's results (which are nothing like the EPA tests) at The most fuel-efficient cars and Best & worst cars review, fuel-efficient vehicles.

The last page of http://www.consumersunion.org/Oct_CR_Fuel_Economy.pdf describes their tests and the old (pre-MY08) EPA tests.

 

Someone already said it but anticipation is a big factor in city driving. Get your foot off the accelerator if you know you will be coming to a stop. You must anticipate other traffic getting in your way,...stop lights getting ready to change,...not accelerating into stoplights. you should drive as if your car has no brakes.

Don't stay on the bumper of the car in front of you. At a light, start creeping forward before traffic starts moving to get a head start.

All of this is conditions permitting, of course..

 

You are getting 47 mpg combined, just shy of the EPA 50 combined on the sticker, which is pretty darned good considering the 17" wheels and lousy city traffic! It'll improve a bit as both the Prius and you get broken in, so relax and enjoy your sweet ride!

 

Welcome to the club! You have discovered part of the fun of driving a Prius! The mpg game.

 

Check your tire pressures. Actually read the tires and inflate a little below the rating. For the 44PSI tires I have, I inflate to 40PSI.

 

Where I live, the traffic is pretty bad as well. My daily commute consists of 8km each way. The first half consists of relatively smooth driving at average speed of 24kmph, and the second half consists of bumper-to-bumper crawl with frequent acceleration/braking at average speed of 12kmph. With a cold start, my mileage has been quite consistently around 5l/100km or 47 mpg. I estimate that the cold start probably contributed to 10% lower mileage.

For the most part, I pay close attention to how I drive and try my best to be economical (e.g. avoid unnecessary braking etc). My worst result was around 30-35 mpg with pretty aggressive (in hurry!) driving in very heavy traffic.