Not enough mileage per gallon

Hi folks!

I own an Honda Civic 2003 Sedan (Sport Edition, which was only available
in Canada I believe).

I am under the impression that the gas consumption has gotten worse over
the last year. I know some maintenance needs to be done to keep the
best gas consumption possible, but don't know what to do exactly.

Any tips or pointers?

Thanks!

Carl

 

Have your PCV valve checked, if it's stuck your mileage will be worse
than normal, sometimes by quite a bit. I don't know how often Honda
recommends replacing it, but it should be done at least every 30k km.

Cosmin

 

Cosmin,

Thanks for the reply!

Forgive me but I'm really dumb when it comes to cars. What's the PCV
valve, where is it, how much is it and can I replace it myself? How
would I know if it needs to be replaced?

Thanks!

Carl

 

+++++++++++++++++++++

Put 34 psi in all your tires, and set your alarm clock to wake you 25
minutes earlier in the morning. If you've been careful to note your
mileage in the 'fuel efficiency chart', what are the ACTUAL statistics?

PCV can be a killer if plugged / stuck open. Don't warm up your engine
in the driveway. Air filter can also be changed by yourself. Obey the
speed limit. A lot of this is in the OWNER'S MANUAL.

'Curly'

 

I concur with Cosmin and Curly re the PCV valve and also especially about
checking the maintenance schedule in your car's owner's manual for what should
have been done to the car.

A few more basic questions to keep this rolling:
How many miles are on your car?
When was the last time you changed the:
-- spark plugs?
-- ignition wires?
-- distributor cap?
-- distributor rotor?
-- air filter?
-- fuel filter? (This might not be do-able or recommended on your car.)
-- engine oil?
-- radiator coolant? And have you checked the level in the coolant reservoir
recently?

All of the above is very basic, inexpensive maintenance for a young car like
yours.

 

If your PCV valve is clogged this soon, then you have other
and much more serious problems with the car. Replace spark
plugs, air filter, etc this early? That was the 1970s when
things had to be replaced every 10,000 miles. For example,
spark plugs are said to be replaced every 50,000 miles. In
reality, plugs at nearly 100,000 should be just fine.

If PCV valve is on your list of possibilities, then so is
EGR valve, throttle sensor, transmission oil, and antifreeze.
You have a mileage drop? One thing lowers mileage by about
10% is discount gasoline that is missing additives found in
brand name gas. My experience is that it takes as much as four
consecutive tanks to undo the mileage reduction from
consecutive visits to discount gas. But then I record every
number. I have also seen where something was maybe dumped
into the gas causing fuel injectors to be damaged. 31 MPG
immediately dropped to 22-25 MPG and car felt sluggish. Honda
found and replaced the defective injectors. I could trace
damage right back to the gas station because I record and
review the numbers.

First, what are numbers from consecutive tanks. Second is
that new gas station shorting you about 8 to 10% of the fuel
they have claimed? I found one that shorted on four separate
tanks. Car took more gallons than even gas gauge suggested and
mileage was proportionally lower. Something about a little
operator switch to set pumps back to normal operation when
Weights and Measures took their readings.

Just too many things could account for a perceived gas
mileage drop. PCV is just the latest hype by some in this
newsgroup. First collect facts. What is the number of miles
and number of gallons recorded for each consecutive fillup?
If PVC valve gets clogged this early, then you have other more
serious problems - not just a PCV problem.

There is very little maintenance required on cars today. And
that maintenance is mostly for long term care. But then your
owner's manual has all that information. Read the manual
first and record you numbers and gas station so that you are
not "feeling" mileage is lower.

 

It's a bit different on all Hondas, but on my old 94 Accord it was on
the valve cover on the rear side (close to the windshield side). It had
a tube going into it, so it was pretty easy to spot. I haven't looked on
my 01 Prelude yet, so I can't say if they changed it. Yours should be in
the same general area.

If you intend on doing some maintenance yourself, if may be a good ideea
to purchase a manual for your car. Haynes and the other cheap ones are
helpfull for minor repairs, but the best manuals are the Helm ones
(www.helminc.com). The manuals will list recommended intervals for
changing fluids and miscelaneous parts that Honda does not. It was my
Haynes manual that listed 30k km as the interval for the PCV valve
replacement.

Cosmin

 

One more item is to watch your driving;see if you are driving more 'city'
miles,or unconsciously accellerating then slowing-back and forth,this
wastes gas.

Keeping tires properly inflated is important,too,just 3-4 psi low affects
gas mileage.

 

Not to step on Cosmin's toes, but I always like Majestic's online Honda drawings
for giving me clues on where a part is.

See http://tinyurl.com/2grb3 item 2, for a 2003 Civic 4-Dr. GX Side SRS. If this
isn't exactly your car, then click on "RETURN TO CHOOSING A SYSTEM\COMPONENT
FOR" and put in the info that identifies your car. Select "breather cover" or
"breather chamber" at the end to bring up a drawing that includes the PCV valve.

Helps to have a new PCV valve in hand when looking for the old one.

You should be able to do a little test on the PCV valve by running the car at
idle and pinching the PCV valve tube (item 5 in the drawings) with a pair of
long-nosed pliers. Keep the tube pinched for at least 20 seconds or until you
hear a little click. The click is the valve operating. See for example the right
column of http://www.honda.co.uk/owner/CivicManual/pdf/11-109.pdf , for
1995-1997 Civics.

Google for "PCV valve" for more discussion. It aids in keeping the engine
crankcase free of blowby vapors by allowing the vapors to return to the engine's
air intake for re-burning. If it is malfunctioning, then among other things the
car's computer may not see the correct flow in the air intake. The car's
computer may run the engine rich (too much gas; not enough air) as a result.

Numerous web sites attest to this.

Of course, as has been noted, many other things may cause poor fuel economy. For
such a young car, I'd be surprised if the PCV valve were the problem.

 

Carl,
I suggest that you get a complete tune-up and a new PCV valve.

 

How do they know that Weights and Measures is checking their pumps? Does
your state announce their inspections?
And how do you know about this "operator switch"? Did you report it to the
State?

Florida does random,unannounced tests;the operators don't even know they're
being tested.

and with that bad gas that Shell was pumping,your gas gauge may be off
anyways.

 

Weights and Measures periodically applies a new test sticker
to the pumps. I am told in some counties, the inspector only
announces his arrival and performs the check. But this is
only hearsay from other gas station attendants. Each county
probably does it differently - a county function; not a state
function. How they test is unknown. However after those
experiences, a number of stations were suddenly exposed for
having that 'secret' switch modification. Was this one?
Don't know. But I do know every tank at that one station was
taking too many gallons per both my gas gauge and from having
recorded every tank. Furthermore, due to the location of this
station, I should have been getting even better than average
gas mileage. What should have been highest MPG also was
suggested by the position of my gas gauge.

I have no doubt that the one station was shorting gas. But
the bottom line and the point of these posts is that one must
record consecutive tanks to really know if gas mileage has
dropped. Other factors can cause a mileage drop.

What is this 'bad gas from Shell' story?

 

What tuneup? In the 70s when manufacturers refused to
install a 1960s technology called electronic ignition, then
tune ups were required every 5,000 miles and less. With
electronic ignition and fuel injection, then recommending
frequent tuneup is akin to promoting a scam. If car needs a
tuneup, then car has a failed part - that should not have
failed. But still some mechanics love to get you in for a
tuneup. Changing spark plugs is simple labor that pays well.

 

Strange,it would seem to be more of a state function than a county one.
In Florida,it's done by the state.One of the local TV stations did a
segment on it a few months ago.

Shell distributed some high sulfur gas in some parts of the country,and the
high sulfur content ruins the silver elements in the in-tank sender,ruining
it. They are paying to have people's senders replaced. A Google search
should give more information on it.

 

Spark plug electrodes DO wear,and they are great indicators of any problem
with an individual cylinder.The rotor and distributor cap electrodes also
wear.