Accord 05 VP Poor Gas Mileage

I bought an Accord '05 Value Package (AT, 5 Speed) in August last year.
Since then I've been trying to measure my gas mileage. The sticker on
the car showed the EPA estimate as 24(city)/34(hwy) mpg. Now, I've been
driving mostly on highways since. I would split it as 70% hwy, 30%
city. Yet, I've been consistently getting 22-23.5 mpg from this car. I
would also like to add that I rarely drive during rush hours on the
highways, meaning I don't brake much once I'm on the highway.

I was told by many people that I should check the tire pressure, as it
could be a major reason for poor gas mileage. I checked the tires and
they all came out to around 26 psi which is way below the 30/32 psi
recommended for the car. So I filled the tires and kept monitoring the
pressure, always keeping it around 32-33 psi cold since November last
year. Still, the mileage hasn't improve at all.

When I took the car to the dealer, I was told that they will not
inspect my car till I had atleast 5000 miles on it, which according to
them is the break-in period (even though my manual says the break-in
period is 500 miles). Then, I contacted Honda directly. The customer
rep told me that no dealer would inspect the car till 7500 miles as
that is the break-in. Then during the conversation he changed the
number to 10000 miles. When I told him that my honda dealer told me
5000 miles was the break-in period, he changed the number again to
4000-4500 miles. It seemed to me that the customer rep was just trying
to make excuses for not checking my car.

Now, I am no expert in cars. So I'm not sure what the typical break-in
period should be. But is it normal to get such poor mileage that I am
getting from my car? I have tried taking all precautions while driving
like slow acceleration, driving at 65 mph on highways and no
overspeeding, driving slow till the engine heats up, no idling the
engine, etc. Is there something I can do to fix this poor mileage
problem? I have driven other cars and never had such a problem so I
know that it's not my driving that could be causing this.

Also, I would like to add that most of my car trips are 5-8 miles long.
Could that be attributing to this problem?

Thanks,
ag

 

How are you measuring your mileage? Fill the tank, reset the trip meter,
drive for how ever may miles you drive then refil when low, divide gallons
poured to fill into miles since odomoter reset?

There are really 2 break-in numbers. The first (typically 500 miles or so)
is the "baby" period. Then there is the long term which is typically around
10k.

This could also play a large part. Your car is spending half it's life not
warmed up.

 

-----------------------------

I read 38 lines before you explained the real reason. You got it.

Short trips suck mileage. Simple.

'Curly'

 

"'Curly Q. Links'" wrote


.. You got it.

They do. My trips are exactly 10 miles long, translating to two 10 mile
in-suburb/city trips each day, 5 days a week; the weekends have short errand
drives, and maybe a couple 15 - 20 mile drives. I am typically getting 27-28
mpg in my '04 Accord with 5-speed AT. When the car was new, I was getting
about 26 mpg driving this same schedule. Maybe a 10 mile trip is
significantly "less sucky" than a 5 - 8 mile trip.

 

I am measuring the gas mileage as you have described. Given that how
everyone feels that trips 5-8 miles long could be the cause of the poor
mileage, is there something I can do for such trips to maximize the
mileage?

Thank you all so very much for your responses.

 

Work further away so your car spends more time warmed up. But then again,
twice the driving at less than twice the mileage wouldn't save you any
money.

Really, your amount of driving isn't really worth fretting over mileage.
See how your car does when it's reached 10k and be happy you are saving
money by having such a short commute.

Could be worse, you could have my commute. My office is 155 miles
round-trip.

 

Probably 20 to 50% less sucky.

Have to agree with everyone that 5 - 8 mile trips are going to involve
a significant amount of the driving in warm-up mode. Also, since
Curly indicates that 70% is highway driving he probably isn't getting
the full benefit of highway cruising since he has to accelerate up to
speed and then only cruises for maybe 4 - 5 miles.

Hey Curley, has it been cold where you are? If so, look for some
significant improvement with warming weather. Also, you should do a
20 - 30 minute trip at least once a week to prevent condensation from
accumulating. That should help your gas milage even though it won't
save you money.

 

Where do you live? Do you live in California or other states where
gasoline is oxygenated in order to help clean up the air? Or do you
live in snow country? Cars don't run as effieciently where there are
freezing temperatures.



East-

 

I live in North Cali. Not too cold actually. It's usually around 50-65
when I'm driving. I do realize that by having a short commute I'm
saving money on gas even though my gas mileage is low. But I really
want to know if it is just the distance or something bigger that is
causing the problem.

Thanks for the input fellas. I will try cruising on some highways for
20-30 minutes everyday for some time. Hopefully I'll see better
results. I'll post my results here soon.

 

California gas has the fuel additve "Ethanol" in it in order to make
the cars run cleaner. The downside is less gas mileage and slightly
less power. Older cars will have their rubber fuel lines corrod and
possibly leak from the additive.

Parts of NorCal have topography. If you have a 4 cylinder in hill
country it will run less efficiently than a more torquier V6 in the
same driving situation. Also cars with automatic transmissions
naturally get less MPG than a car with a standard 5 speed manual.



East-

 

Also cars get less MPG during their break in period. The seal from the
pistons rings between the combustion chambers and crank case still
needs to break in/strengthen up first.



East-

 

Like you said, my car is spending half its life not warmed up. Does
this negatively affect my car besides the low gas mileage? Can this
cause problems with my engine?

 

Yes. If the car never reaches operating temperature than there will be
nasty carbon deposits inside the cars combustion chambers. The valves
themselves will become coated with carbon, as will the spark plugs and
injectors.

That's one reason why cars that do lots of highway miles instead of
short city trips last longer.

East-

 

Combine trips? I.e. do all of the short trips together, so that the
first short trip leaves the car still warm for the next one.

In your previous car, how did your fuel economy compare to the EPA
fuel economy?

 

but how fast do you go? the best mileage is going to be given AS SOON AS
5th gear kicks in, with the revs as low as possible.

shouldve improved some, but maybe not measurably.

theyre all right. if the car is babied, it might not be broken in until
after 10k miles. or later.

google for "EPA estimate test procedure" and youll find how they do it.
your mileage may vary, and it is.

time, and longer trips

yes. the car likely isnt warming up enough to run as lean as it can.

 

not really. another issue might be "reformulated gas" if you live in an
area that uses it. mileage on RFG is lower than normal.

 

theres a slight possibilty your catalyst and O2 sensors wont last as
long as they could.

 

its perfectly normal, especially considering the car is still breaking
in. if theyre using RFG up there thats another factor.

 

Not really. Installing a coolant heater will make a big difference.

 

*Significantly* less in some cases, rather, after fifty thousand miles of
mechanically sympathetic use, my own cars have been "better" for it (lower
fuel consumption being the main area).