2008 minivans: Honda Odyssey vs Toyota Sienna

You're sure it's in that order?

 

Consumer Reports says Sienna gets 19 in mixed driving just like my Odyssey.
Unfortunately I drive mostly around town in it and not on highway so it
averages Odyssey averages 17. Meanwhile my wife gets easily 34 in Camry
hybrid, city or highway, just as EPA figures indicated.

 

Figures match my 2006 Odyssey perfectly.

It may get that on a long trip, but for day-to-day driving...

From Consumer guide Automotive

Forget the EPA. Consumer Guide's auto editors drove 150,000 miles
last year. We drove to work, to day care, to the grocery store, and on
vacation. We drove through record heat, blinding snow, driving rain,
and confounding road construction, keeping track of every drop of fuel
we used along the way.

The EPA admits its fuel economy numbers are estimates. Our numbers are
real. A typical Consumer Guide test car is evaluated by at least four
editors, all of whom account for their individual fuel usage. Here are
the vehicles in each class that used the least amount of fuel while in
our care.

Honda Odyssey-16.4 MPG

Toyota Sienna-16.4 MPG

http://consumerguideauto.howstuffworks.com/2008-fuel-economy-champions.htm

Consumer Reports faired a little better with 19 MPG.

As one poster noted about the Odyssey

"my normal gas mileage is 17 mpg in the city and 24.5-25 mpg on the
highway. I've gotten as low as 15 mpg in the winter here (10% ethanol
fuel) and as high as 27.1 mpg on the highway (traveling by myself with
just two suitcases). I keep my tires at 37 psi, which is what made my
gas mileage increase by 1-2 mpg."

Another noted about his Sienna " I drive 80MPH and still get 24 MPG"
which I will dismiss as total BS.

 

My Odyssey has a onboard computer that I verify every fill up. It gets 17
around city. Never better around town. End I have the more efficient
engine that turns off 3 cylinders during coasting. I believe they may have
a new version that can turn off 4 cyclinders in the Accord. Not sure if it
is in the Odyssey though.

 

/all/ modern fuel injected cars turn of /all/ cylinders when coasting.

it's /some/ cars that turn off cylinders when /cruising/.

 

My Sienna gets 25-28 on a trip. It may be hard for people to believe,
but not for me as I own and drive one and have checked it on more than
one trip. That is the way it is.
--

 

snip

Mind explaining what you mean? By coasting do you mean rolling with
the gear shift in neutral? If that is what you mean is engine cut out
in this condition a requirement of North American autos as it
certainly isn't so for European vehicles. In Europe it is becoming
increasingly common for modern vehicles to stop the engine when at
rest and for the engine to restart when the gas pedal (accelerator) is
depressed.

 

no, coasting is when the momentum of the vehicle pushes against the
engine and turns it even when you have your foot off the gas, like
descending a hill or slowing to a stop.

no, it's for all electronic fuel injection vehicles, globally. the
forward energy of the vehicle is rotating the engine - there's no point
injecting gas when the motor's just pumping air coasting.

that's not coasting.

 

Uh boy, another topic introduced! ;-)

Re: the regular/super debate - here in NJ, we have regular (87), plus
(89) and super (91/93). My Audi A4 turbo requires "super" - 91 octane
- although I have run it with no issues on 89. My wife actually filled
it with regular (87) once and it definitely was down on power. Don't
recall the gas mileage (although I have it in my log). I can imagine
some small towns (which is where I assume dbu lives) which don't carry
all 3 grades. I've seen that in Maine, but if they have 87 and 89,
it's still labeled 'regular' and 'plus', not 'super' for 89. And who
uses 'Super' for their lawnmowers, etc?? I use the cheapest crap I can
find, just like for the Odyssey. ;-) I filled it up yesterday for
$3.83 (full serve, too, which is all we have in NJ).

Dan D
Central NJ USA

 

Actually, I was in Colorado a couple of weeks ago, and all the gas there
seemed to be a couple of points lower in octane than what I'm used to in
Texas. I don't know why -- something to do with the altitude, maybe? Alas, I
have no photos to support my assertion.

 

I read through this thread with amusement and I believe dbu. There is a
Sunoco gas station here in Baltimore County, MD. It was on York Road, by
Seminary Avenue in an area called Lutherville. They sell Premium at the
same cost as mid grade. It used to be a Mobile station before they changed
maybe over a year ago, but apparently same owner since they were doing this
when they were a Mobile station. They have mechanics bays and a very small
convenience section.

Why do they do this? Don't know - maybe to get people to buy gas, get to
know them and maybe have their car worked on by the mechanic? I don't ask,
but used to buy gas there in my previous car when I used premium. Also had
the car worked on by the mechanic before. He's a decent mechanic. If
you're ever in the area and want to see for yourself, swing by. They've
been doing this at least for the past 5 years. And no, I'm not going to
take a picture - not worth the time, but it is a brand name gas.

-Dave

 

"Dave L" ...

Back when I was in HS and College I worked at a Shell station in Middletown
NJ. This was at the time gas was about 50 cents per gallon. Whenever we
ran out of regular [and it happened many times] we were instructed to lower
the price of premium down to the regular price so the customers wer not
pissed off that we had none of their gas. They were always really happy
about this. This was when the price was regular, 2 cent more for midgrade
and 4 cent more for premium.
Tomes

 

I'm well aware of that.

Re coasting: the definition is simply forward motion due to force of
gravity, I think you have added the bit concerning engagement of
engine with drive train.

With respect to the engine cutting out (either by gas cutoff or
ignition cutoff or both) when the torque is reversed (vehicle driving
engine), this is something new to me and I am pretty sure that doesn't
occur in my Civic (2005) or in any other fuel injected vehicle I have
driven worldwide. I take your point that there is no gain by
injecting fuel under these circumstances. How does the engine detect
'torque reversal' to cutoff fuel and ignition? Does this occur each
time you brake as braking is a 'coasting' event the way you define it.

Incidentally what is 'electronic fuel injection' the converse of which
is, I assume, 'mechanical fuel injection'. If you mean a carburetor
in my 'parlance' a carburetor is an induction system not an injection
system re Collins English Dictionary 'induction'.

 

why gravity? coasting is coasting - taking your foot off the gas while
you're moving.

i did.

you can cut off ignition, but i'm not aware of anyone who does - what's
important is shutting off gas.

it absolutely does. the point is, when you're coasting, you're
primarily pumping air. not point injecting gas in that situation.

rpm and throttle position.

modern computer controlled electronically activated fuel injection.

if i'd meant carburetor, i'd have said carburetor.

 

Yup, I remember when the spread between regular and premium was much smaller
than now. When did gas stations start coming out with mid-grade? I thought
it was more recent than the gas being 50 cents.

-Dave

 

"Dave L" ...

Now I am trying to remember better (ouch). I think that the mid-grade was
the unleaded right when unleaded came out, and the regular and premium were
leaded. This was 1975-8ish.
Tomes

 

http://en.wikipedia.org/wiki/Octane_rating explains that lower octane
works OK in high altitude.

 

OK, then restating my previous question, what is the converse to
electronic fuel injection in a gasoline engine. Mechanical fuel
injection is the normal system for diesel engines but not, AFAIK, used
for gas engines.

As I understand it you are saying that during the period when
'coasting' to stop no fuel is being admitted to the engine. If this
correct at some point fuel must be readmitted to allow the engine to
idle when the vehicle is at stop. The question is how does the
'system' determine when fuel is to be readmitted during the coasting
event to prevent the engine from 'stopping' when at rest?

Incidentally rpm and throttle position does not indicate torque
reversal (coasting) as you have implied.

 

the old bosch systems were pretty much mechanical. remember the ones
with the braided line that ran to each cylinder?

the computer monitors rpm's and starts re-injecting below a base
threshold. older systems, that's about 1500rpm. according to tegger,
more modern systems cut it to as low as 750rpm.

then you need to think this situation through one more time - there's no
situation under which you can have high rpm's and a closed throttle
unless you're coasting.

 

Let me get this straight. I think you are claiming that the engine uses
*NO FUEL* during coasting...., right? So, let's think of an example....
If I was coming down a large mountain, on the Interstate, at 65mph, and
was to *COAST* for 20 miles (entirely realistic in some places), you are
saying that I would not use ANY FUEL? Right?

My take on that is that it's absolutely wrong. The engine is still
running, even if it's not doing any real "work". It is using fuel.