I am on my third tank and so far the highway mileage was almost at EPA: around 36 mpg. But city mileage was dramatically lower than EPA: way below 30mpg. Any ideas?

 

Ya, I don't know why they list it city being better as it is also my experiance with highway producing the good milage.

 

City mileage from the EPA is optimistic,whereas, I can always get better mileage on the highway than the EPA.

There are many factors which affect city mileage. One very important factor is the miles driven. When I take short trips in the city, the mileage is dramatically lower than if I drive for 20 or more minutes.

If everything is warm such as when I drive on the highway and then on the city, I sometimes even get EPA city mileage. A warmed system is better than one that just started up.

 

Same here - I have a 7 mile city commute and I've been a hair under 30 in my 2,000 miles. Doesn't seem to be much I can do...still, I only have to get a tank of gas like once a month.

 

H2O Doctor is correct, if you live in the north, colder temps will adversely affect city mileage because the engine must run to keep the emissions systems up to operating temps plus you may be in a state that mandates 10% ethanol (lower mpg). I believe that toyota hybrids' city mpgs are based on more EV mode vs combustion mode, (better fuel economy in city). Whereas, at highway speeds, the engine stays nice and warm all the time no matter what the ambient temp is. Could be other factors such as driving style but you will have to address them based on personal preferences.

 

I posted this in another thread on the same subject. Most of the time the reason that you do not achieve current EPA fuel economy values is due to forces outside your control. Some factors are certainly within your control though.

Factors affecting your FE ( and everyone else's also, btw ) in decending order of importance...
1) Towing anything is a huge penalty possibly as much as a 50% reduction in FE
2) Lots of weight in the vehicle, passengers cargo etc. ( EPA tests are done empty )
3) Short trips under 10 min - deduct 20% from your 'Norm'
4) Snow, Rain, sleet - deduct 15%
5) Strong head wind - deduct 10%
6) Cold weather - deduct 5 - 10%
7) High speed driving 0ver 70 mph - deduct 5 - 10%
8) Many starts from a dead stop ( going from stop sign to stop sign to stop sign ) - deduct 5 - 10%
9) Terrain - fortunately 'what goes up..' usually this balances out on a RT
10) Winter fuel - deduct 2 - 5%

Now these are cumulative, so short trips with a lot of stops ( -20% )( -5% ) in winter ( -7% ) on slick pavement ( -15% ) can result in as much as a 40 - 50% loss from your personal 'Norm'. The bright side of this is that your 'Norm' is higher than most others at 39 mpg. If your Norm was only 26 mpg for example you might expect to get 13-15 mpg.

This is really really important when you consider how much more fuel you use in cold weather but also how much less you use relatively to a an ICE-only V6 driver. ( See below )

TCH 'Norm' @ 39 mpg uses 25.6 gal per 1000 mi driven
TCH 'Winter' @ 25 mpg uses 40 gal per 1000 mi driven

ICE 'Norm' @ 26 mpg uses 38.5 gal per 1000 mi driven
ICE 'Winter' @ 15 mpg uses 66.7 gal per 1000 mi driven

In 'Normal' driving an ICE driver will only use about 13 gal more than a TCH driver for every 1000 mi. In 'Winter' however, that ICE driver will now use over 28 gal more than a TCH driver for the same 1000 mi.

Enjoy your hybrid . It will be Spring soon.

 

See Factor #3 below. With a 7 mi commute you are just getting to optimal engine, fluid, cabin, catalytic converter temperatures at the time you arrive at your diestination. Then you shut it down for another extended period.

Other than towing, short trips are the least efficient way to drive any vehicle.

 

Here are several ideas to consider about achieving better Fuel economy.

While some factors are outside the control of the driver such as weather, terrain and the inherent limitations of an ICE vehicle many certainly within our control.

Short trips: As noted below by several these are death on fuel economy. Plan ahead and combine short trips into longer ones.

'City driving': This is very very amorphous. Your view of city driving may be much different than mine. Is it...
.. crawling out of Manhattan in rush hour at a constant 15 mph?
.. stuck rolling slowly in the DC Beltway?
.. picking up the children in your local neighborhood?
.. rolling through heavy Holiday traffic in a surburban mall?
.. coming home from work, getting off the freeway and going from stop sign to stop sign to stop sign in your neighborhood?

'Why is my average fuel economy not between the Highway and City number.' Two words: 'weighted average'. If you avoid city driving as much as possible because it's too much stress, takes too long, etc then your personal weighted average will be much closer to the Highway number - adjusted for factors outside your control as noted previously. Someone who chooses to drive as much as possible off the highway will get the advantage of the better fuel economy in 'City' criving.

Most of us choose not to take the most fuel efficient route!! Consider, you are on a highway coming up to a medium sized city where the highway loops around the city. To get the best fuel economy one should choose to get off the highway, get onto the city streets, drive at a slower speed then pick up the highway on the other side of town. Yeah but.. 'I could get stuck in traffic in the city and it's a lot slower driving and it'll probably take longer.' All true statements. But it is more efficient to drive in this manner. However in the end it is your choice.

As wvgasguy has pointed out several times, in absolute terms the amount of fuel you will save by taking the more efficient route occasionally is relatively insignificant. Dont obsess over it. However on a regular basis it is more fuel efficient to slow down, consider an alternate non-highway route that may take a little more time, where you can use the hybrid's features to the most advantage.

 

While that might be the most fuel efficient method in a prius, I have found that in my TCH, the best FE is by staying on the highway and driving between 55 - 65 MPH. I have tried 45 MPH no stops, and tried "city" driving, but the best FE numbers I have ever gotten were from "light highway driving". I don't know why the TCH would respond so differently than a prius, but it looks like there might be a diference. It might be the fact that the Prius is lighter, making the FE numbers better for slow driving, or it could have somethnig to do with aerodynamics, but either way, I think slower highway is the best for a TCH.

 

Amen on that!!