Better MPG in the City vs. Hwy

[Loren]

I consistently get better MPG in the city than I do on the highway. Anybody else have the same experience?

I'll clarify:

My city driving is mostly fairly short trips, 10-20 miles at speeds from 35-50 mph. Long enough to get the car warmed up, and I usually know where I'm going enough that I can time the lights and get a lot of DFCO coast time without a lot of sitting at the lights idling. I can usually pull between 44 and 48 mpg on most of these trips. If traffic is particularly bad or the trip is less than 5 miles, it might sometimes be as low as 38, but I've gotten better at managing traffic, so it's rarely under 40 any more. This is punctuated with occasional longer trips at 60-65 mph for maybe 20-30 miles, which net just a little less mpg. Typical tank mpg will be around 45 mpg.

When I speak of highway driving, I'm talking typical interstate at 70 mph. It's all I can do to pull 43 mpg on the interstate. Which isn't bad, I guess, but flies in the face of most people's logic that you should get better mileage on the highway.

Now, if I take back roads, 2-lane highways where I can cruise 55-60 instead of 70, and make use of more pulse & glide, I can usually get up to around 48-49 mpg. And by the time I'm home (adding in some slower city driving with the car fully warmed up), the trip average will often be between 50 and 54 mpg.

So, no Earth-shattering conclusions here. MPG is directly related to speed, and DFCO can pay huge dividends in city driving.

[1.5]

First of all, how in the hell are you getting such amazing gas mileage?? Since u live in the Tampa Bay area I can use street names lol. I live in Tampa and drive mainly Dale Mabry everywhere I go. There are like 7 lights in the 2-3 mile stretch I drive everyday and then I usally get on Ehrlich which is another nightmare of traffic and lights. I average bout 35-36 mpg.

I do however agree that highway driving yields even worse mileage. On Tuesday I drove from Tampa to Pensacola which is ~900 mile round trip. I filled up a couple times and when driving 70-78ish and slwoing down for small town I averaged 35 mpg. On the highway I took a leg at 75-80 and I average 33mpg and then on the trip back I did a leg at 85-95 and averaged 27mpg.

Now I think a large part of the decrease in mpg is due to the lack of cruise control. Cruise control would hold the engine at a desired speed and reduce the accelerating and decelerating done because your foot moves around naturally on the pedal.

The trip still did prove that city driving, because of its lower speeds and ability to coast in neutral, actually yields better gas mileage than highway driving.

P.S I also got a $276 speeding ticket during the leg that I was doing 85-95. I was caught by an aircraft and not ticketed until about 20-30 miles later. 91 in a 70. DAMN!

[why?]

you don't want to coast in neutral, coast in gear so you can take advantage of DFCO. It really helps a ton. Also, what are your wheels and tires?

[BailOut]

Hi Loren,

You've experienced what tests have consistently shown in that speeds above 55 MPH experience a much larger amount of wind resistance than any lower speed, and that anything approaching 68 or higher experiences an even higher, seemingly disproportionate amount of wind resistance.

When you couple that huge amount of wind resistance with the higher RPM needed to maintain the higher speed, the result can be nothing but a big MPG hit.

This is why I live in the right hand lane and simply do not drive faster 55 MPH on the highway.


@1.5: If the driver has a modicum of attention and throttle control then cruise control actually makes things worse. This is due to the way it first allows the car to lag behind the target speed, then aggressively uses the throttle to catch back up in a hurry. I call this "the slinky effect".


@why?: Unfortunately, DFCO versus coasting isn't as simple as "always use DFCO". If you have a long distance to go, or are pulse and gliding, then coasting is much better than DFCO due to having much less drag. Conversely, if you're leaving the highway via an exit ramp, or are headed to a red light a short distance away, etc. then DFCO is the better option.

[127.0.0.1]

those numbers are impossible on a stock configured 2007 US model yaris
what you are using to measure mpg is inaccurate for some reason.

it is all downhill, or you are doing zero stop and go. I suspect it is all go and downhill.
or these are momentary readings, not tank averages. only tank averages really
matter when claiming amazing MPG.


Or....what are your modifications from bone stock ? srsly...

[thebarber]

Originally Posted by 127.0.0.1

those numbers are impossible on a stock configured 2007 US model yaris
what you are using to measure mpg is inaccurate for some reason.

it is all downhill, or you are doing zero stop and go. I suspect it is all go and downhill.
or these are momentary readings, not tank averages. only tank averages really
matter when claiming amazing MPG.


Or....what are your modifications from bone stock ? srsly...

lol, you must be new. bailout is the man when it comes to hypermiling...and loren doesn't seem to be a slouch either!

[Loren]

Originally Posted by 127.0.0.1

those numbers are impossible on a stock configured 2007 US model yaris
what you are using to measure mpg is inaccurate for some reason.

it is all downhill, or you are doing zero stop and go. I suspect it is all go and downhill.
or these are momentary readings, not tank averages. only tank averages really
matter when claiming amazing MPG.


Or....what are your modifications from bone stock ? srsly...

Dude, put a name in your sig, I refuse to refer to you as a generic IP address!

Now, just because you can't or haven't done it doesn't mean that it's impossible. My Yaris has mods, but they're all performance mods intended to help autocross performance. Specifically, I have a DC header, an aluminum crankshaft pulley, a removed back seat, and 15x7 wheels (11 pounds each) with 215/45-15 performance tires.

I'm not quoting "instantaneous" readings from a downhill coast, my friend. If I were, the readings would be "9999" because the car goes into DFCO in that condition and uses NO fuel. I'll sometimes quote trip mileage for discussion because if I can do it for a 20-mile trip, it stands to reason that a person could (as BailOut regularly does) do it all the time. My tank averages are, as I have stated, usually around 45 mpg. I did do about a half-tank (250+ miles) hypermiling trip once and achieve 49.9 mpg, and I'm sure I could do better than that now.

My city mileage is better than highway mileage largely because I can usually manage to make the "stop and go" traffic work FOR me. Accelerating very slowly, and coasting in DFCO for as long as possible, avoiding STOPPING by starting the coast early enough that I might be going 20 mph when the traffic ahead starts moving again.

It sometimes pisses off people behind me who don't "get it", but I invariably reach the same place at the same time as the people who are driving like jackrabbits from light to light.

[Loren]

Originally Posted by thebarber

lol, you must be new. bailout is the man when it comes to hypermiling...and loren doesn't seem to be a slouch either!

I don't take it nearly as seriously as BailOut does, it's just an interesting game to me. That said, the more you do it, the better you get at it... like any other game.

[Loren]

Originally Posted by 1.5

First of all, how in the hell are you getting such amazing gas mileage?? Since u live in the Tampa Bay area I can use street names lol. I live in Tampa and drive mainly Dale Mabry everywhere I go. There are like 7 lights in the 2-3 mile stretch I drive everyday and then I usally get on Ehrlich which is another nightmare of traffic and lights. I average bout 35-36 mpg.

Heh, Dale Mabry is interesting. I don't drive it often, but I find that as long as the traffic is moving (not a post-game or rush-hour standstill), I actually get some of my best mpg there. The lights are spaced way far apart, you can see them from a long ways away, and there are enough lanes that you can drive slowly and let the idiots (who are just going to STOP at the next light that's already red) zip by me. LOTS of DFCO coasting on Dale Mabry when the traffic is moderate. Ehrilich is much the same, except it has curves that keep you from seeing the lights from a distance in some places.

We need to hook up, I can take you for a drive and show you a few things. We can even pull the ScanGauge and put it in your car, if you want. Would be interesting to experiment and see how much we can improve your MPG just from driving techniques learned in 30 minutes or so.

I think I'm free this weekend. PM me if you want to try to get together.

[127.0.0.1]

Originally Posted by Loren

Dude, put a name in your sig, I refuse to refer to you as a generic IP address!

Now, just because you can't or haven't done it doesn't mean that it's impossible. My Yaris has mods, but they're all performance mods intended to help autocross performance. Specifically, I have a DC header, an aluminum crankshaft pulley, a removed back seat, and 15x7 wheels (11 pounds each) with 215/45-15 performance tires.

I'm not quoting "instantaneous" readings from a downhill coast, my friend. If I were, the readings would be "9999" because the car goes into DFCO in that condition and uses NO fuel. I'll sometimes quote trip mileage for discussion because if I can do it for a 20-mile trip, it stands to reason that a person could (as BailOut regularly does) do it all the time. My tank averages are, as I have stated, usually around 45 mpg. I did do about a half-tank (250+ miles) hypermiling trip once and achieve 49.9 mpg, and I'm sure I could do better than that now.

My city mileage is better than highway mileage largely because I can usually manage to make the "stop and go" traffic work FOR me. Accelerating very slowly, and coasting in DFCO for as long as possible, avoiding STOPPING by starting the coast early enough that I might be going 20 mph when the traffic ahead starts moving again.

It sometimes pisses off people behind me who don't "get it", but I invariably reach the same place at the same time as the people who are driving like jackrabbits from light to light.

mods.

--->It sometimes pisses off people behind me who don't "get it"<----
yeah that will always happen

[SpaceShot]

I have found that my best MPG is on small town 2 lane roads, 10-15 miles over to stores in the next town or something. 45-47 Mph seems to be sweet spot if you can hold it for an entire trip.
Closer to 40 Mph, and my frustration and accelerating uphills starts to eat away any further Mpg gains.
The better you know the route the better you anticipate hills and stops and where you will find heavier traffic, which all factors in to the average for the trip.

About once every 3rd month, I make a concentrated FE run and try to break my trip record of 54.
For my daily commute I have settled in and accept getting the 39 - 45 Mpg as it happens to go.

It took a year of practice with a ScanGuage to get from 37-39 averages to 40-45 on my commute, but it is still very doable with a base Yaris.

[1stToyota]

Originally Posted by 127.0.0.1

those numbers are impossible on a stock configured 2007 US model yaris
what you are using to measure mpg is inaccurate for some reason.

it is all downhill, or you are doing zero stop and go. I suspect it is all go and downhill.
or these are momentary readings, not tank averages. only tank averages really
matter when claiming amazing MPG.


Or....what are your modifications from bone stock ? srsly...

Is there a difference with the 2008 US model?
Guess you could classify me as the anti-hypermiler because I almost never get below 65 mph on the highway, up to 80+ mph once in a while, run stock psi in my tires, never coast in gear, run the A/C-Defroster more often than not, etc...and almost never drop below 40 mpg [tank averages, of course], usually average around 42 mpg. I do use 100% gas about 99% of the time. And no hills around here to coast down, mostly flat. Car is bone stock 2008.

[DevilGirl]

Originally Posted by 1stToyota

Is there a difference with the 2008 US model?
Guess you could classify me as the anti-hypermiler because I almost never get below 65 mph on the highway, up to 80+ mph once in a while, run stock psi in my tires, never coast in gear, run the A/C-Defroster more often than not, etc...and almost never drop below 40 mpg [tank averages, of course], usually average around 42 mpg. I do use 100% gas about 99% of the time. And no hills around here to coast down, mostly flat. Car is bone stock 2008.

No hills = better mpg's

[1stToyota]

Originally Posted by DevilGirl

No hills = better mpg's

I just said that because 127.0.0.1 seemed to suggest that Loren's good numbers probably resulted from downhill coasting.

[Loren]

Originally Posted by 127.0.0.1

mods.

Are you implying that my minor performance mods are responsible for me getting 40% better than EPA mileage?

Believe what you want, I'm not going to argue with you. But, I guarantee you that an experienced hypermiler could get in YOUR Yaris as it sits right now and return 45 mpg any day of the week.

[talnlnky]

My drive to work is a great example that mimics what you see loren. Commute is 9.2miles on 25-45mph (85% is 35-40) city roads or 11.3 miles highway @ 55-60mph. Both take approximately 20-25 minutes depending on traffic.

In the summer I've reached up to 55mpg on the city route, and around 45 on the highway route.

In the winter however, city route & highway route are fairly similar at 37-42mpg. The city route in the winter gives poor performance unless I only shift up into 4th gear (don't used 5th at all) because it doesn't heat up fast enough. The highway route however heats up to 186F in the first 2 miles.

I still use the city route, unless I need to make a special stop, or feel like driving faster.

I think in a perfect world, all driving would be at 30-45mph. 4th gear at 30-35mph can still net good mpg's.

[talnlnky]

Originally Posted by DevilGirl

No hills = better mpg's

Sometimes. My best highway speed tanks have been while driving up & down hills.

It's all relative... There is one section of highway however that I consistently get the worse gas mileage on it even though it is a slow downhill slope for many miles. There is a head wind that could cause a yaris to hop two lanes if it gets hit by it on the side.

[Loren]

Originally Posted by talnlnky

In the summer I've reached up to 55mpg on the city route, and around 45 on the highway route.

No way! How can you makes such outlandish claims? There's no way a stock Yaris can do that!