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Comments
I think this MIGHT have been true when the majority of cars used carburetors.
(whole technical explanation here: short version, EFI now have MAF's... SO the emphasis is (but has ALWAYS been) on CLEAN AIR)
On Honda Civic specifically:, oem recommendation is @ 30,000 miles. I did it @ 60,000 miles. I will do it again at the next 60,000 miles interval @ 120,000 miles by the speedometer. :shades:
You will NOT see this written in the technical data (shop manual)....BUT...
When you do the R/R, DO NOT undo the air box to "CHECK" the condition of the air filter UNTIL the NEXT change!! . When you do that, you so called unseat the seal/s and increase the chances that the area/s around the seals will leak dusty "dirty" air to the clean side. The only valid "check" is the ppm silicon reading (aka dirt/sand) on a UOA and you can not "SEE" that. Also MOST folks do not do UOA's. A clean air filter is DESIGNED to get dirty.!!!???? So what is surprising about seeing an air filter dirty?...its just doing its job, boss!!!
To make a long story short, on our daily commute BEFORE air filter change; 38-42 mpg, AFTER air filter change:38-42 mpg.
(Using the 15% improvement metric, it shoul have been between 43.7 to 48.3 mpg...NOT! )
Counter intuitively because of the MAF (emphasis on CLEAN air) a filter that is slightly to moderately "used" actually filters BETTER than when new. When new, it actually lets in more harmful particles than when "used"
While many folks and even some filter manufacturers would like you to believe that a cleaner or less restrictive filter will improve fuel economy, that simply isn't the case. Why? Simple, all fuel injected engines weigh the intake air (or more specifically they measure the density of the intake air), and adjust the fuel injection system to meter out exactly the precise amount of gasoline required for the current power requirements, no more, no less. If your filter is dirty and restrictive, and limiting the amount of intake air, the fuel injection system simply cuts back on the fuel injected. The net result isn't that your engine runs richer; it's that your engine will be able to develop less power at wide open throttle.
Looked at another way, lets say that at half throttle with a clean filter your engine is able to ingest say 200 cubic feet per minute (CFM) of air. Assuming that's the case, and assuming that your engine runs slightly richer that stoichiometric, the engine computer will meter out just enough gasoline to create an intake charge with ~14.5 parts of air (by weight) to 1 part of fuel (also by weight). Let's now say that you've driven that engine say 100,000 miles without changing the airfilter, and now at half throttle, the atmosphere is only able to shove in 100 cubic feet of air per minute. Under this scenario, you might need to apply three quarters throttle (or more) to allow your engine the full 200 CFM of air you need for any given amount of acceleration.
The important thing here is that regardless of the throttle setting, your engine computer is simply looking at the weight of the air in the intake plenum and is simply metering out the proper amount of fuel for the air present. Long story short, regardless of whether you're using half throttle or wide open throttle to get any given amount of air into your engine, the fuel injection system will meter out the proper amount of fuel, and your fuel economy won't change one bit.
Best Regards,
Shipo
Well that seals the deal. I will stick with what the manual says. Thanks!
The car hasn't had it's first oil change. Plus we have had winter fuel. I swapped out the winter tires Nokian WRG2's for the all season Michelins that come with the car, the mileage dropped to 29 mpg on the highway. Once the stock tires are burned up I'll probably run the Nokian all seasons year round they feel really good in all conditions and have 50k mile warranty.
Better economy. So far the fuel economy is on par with the new EPA figures and I drive about 75-80 mph on the highway.
I live in oil country (Louisiana) and even our prices are in the 3.60's. I almost want to feel sorry for all those people driving new trucks and SUVs, but they knew this was coming.
Be that as it may, I consider the Honda LX with 5 spd manual, one of the quintessential economy cars. (gasser)
1st fill-up: 35.68mpg (was on gas from the dealership)
2nd fill-up: 36.85mpg (premium)
3rd fill-up: 38.58mpg (premium)
Not bad for a car that's supposed to do 34 highway according to the EPA.
My daily commute is about 35 miles each way, probably 80% highway. I generally do 75+% highway. I have been using the Civic's cruise control as much as I can when at speed (*I* get it to speed with a light foot), not on hill climbs, and only when there's relatively light traffic.
I have found that I needed to "learn" how to drive for best fuel economy. I recently had an Acura TSX loaner for a day, and it had a trip computer with "Instant Fuel Economy" and "Average MPG". I found that if I was light on the pedal, sticking to the speed limits, feathering it on the highway and not being in a rush to get it up to speed around town or when merging onto the highway, the average fuel economy for the TSX read 34-35mpg. I was SHOCKED! Since the Civic doesn't have a trip computer (booooo!!! :frown:), I have purchased a ScanGaugeII, which--hopefully--will continue to "train" me how to drive for best fuel economy. (The ScanGauge should give me the same information as the TSX's trip computer.)
I expected the Civic to get 34-37mpg (I owned a '95 Integra prior to this, and it got 30-32mpg despite my slightly less fuel conscious driving habits and highway EPA estimates of 28-29mpg). I was happily surprised to see 38+mpg on my last fill-up with the Civic. But please note that part of this is due to my "re-training" and rethinking how I drive, the fact that I do a lot of highway, warmer weather (springtime), and *maybe* my use of good premium gas (which many people say is a waste of money...well, my last car had 255,000 miles on it with premium gas, regular maintenance at the dealership, and DuraLube, so I know where I stand :-) ).
Oh...The BIG digital speedometer that EVERYONE around me can see does help keep me honest about driving more sanely. :-) Hey, if that saves me a few bucks at the pump or lets me go a few more miles before tanking up, I'm all for it!
...kl...
But to each his own...but you should really do a test to see if what your routine is really has the validity that you claim.
The Sandman
Regarding Duralube, saying that you believe in it because your last car went 255,000 miles with it is kind of like saying because my Grandfather took a single shot of Jack Daniels every day (even during prohibition, -he bought many cases before that silly law ever took affect-) and lived to something over 110 (nobody was ever able to prove when he was born), that that's was made him live so long. Sorry, not buying.
Best Regards,
Shipo
Good to see since I haven't driven it in a year and the mpg hasn't changed.
Great car. The Drive by wire is lame though.
I like Duralube but not for my engine. I use it instead of WD40 which is just fish oil.
They sell it in a spray can and it really works miles better than WD40. I'd never put it in my engine as an additive but on hinges or squeaky rusty things it's fantastic! :shades:
Best Regards,
Shipo
Civic 06 ex auto
My last three fill ups:
47.7mpg
41.4mpg
49.5mpg
All are with AC (I live in AZ).
The 49.5 is a real fluke probably but I've seen many in the 45s.
My historical number has improved significantly in the past year when I "slowed down" but the car is still getting better! Last six months I've averaged 43/44mpg in all driving.
Anyone else out there doing this well or have I found a real jewel? I'm taking it into service next week to see what the techs think....I just had the plugs replaced and I swear it's made a huge different.
You might want to tell Honda the same thing. Your mileage is excellent.
Kip
"This class of car" is a minority position of the passenger vehicle fleet @ less than 25%. However it may rise as a result of record prices for Rug to PUG. The official statistics will take 1-2 years to hit publication. I would not hesitate to do what you are thinking. I run 35 psi, the high speed psi recommendation in the owners manual. On another car I run 38 psi and the tire is approaching 107,000 miles and the tread wear is dead even across the width. All the best.
Best Regards,
Shipo
That said, you can use Regular gasoline with up to 10% ethanol (which is what most regular gasoline is now anyways).
By switching away from e85 and back to regular gasoline you should get an mpg boost (particularly in the winter) as your car gets used to the regular fuel again.
#1 26 mpg - 3 gallons to full
#2 25 mpg - 4 gallons to full
#3 24 mpg - 7 gallons to full
Mostly all city driving with a jump on the highway for a few miles each day. Of course my car only has 350 miles on it.
I must admit my 2000 Honda Civic LE auto gets slightly better mileage at 27 mpg consistently on the same route-back and forth to work and grocery store.
Will be anxiously awaiting a road trip to see the better numbers. :shades:
I drive mixed highway and city (70%/30%) and avg 74mph on the highway. I'm not what you'd call a gentle shifter, usually hitting 4000-4500 at shift points below 4th.
Used to be lucky to get 35.5 mpg max during the hottest week in the summer until I changed tires. Had Michelin X Radials installed last Nov and immediately gained 10% in MPG. Had used Firestone Infinity in the winter and Kumho Ecxtas in the summer for the last 3 years.
In my experience cruise control is only good when the terrain is flat. I can do a much better job in dealing with hills controlling the gas myself. In most cases I can avoid the downshift and stay in OD. Cruise control can't anticipate hills or back off the gas to avoid a downshift. That's why I noted that your terrain might have an effect when using cruise control. Lots of downshifting out of OD will be detrimental to your mileage. I also try when starting to keep the shift points of the AT to 3000 rpm or below. This is the sweet spot for maximum mpg when starting up.
I only added 5.39 gallons so my next fill up I drove about 85% highway with the A/C on and through mountainous highways (I live in the endless mountain range area) and about 15% city. I got 36.3 mpg. I am very happy with that as my terrain is not very flat!
Try it out sometime.
FWIW, I believe that the high fuel prices we're experiencing are a self correcting problem and has less to do with the speeds that folks drive, and more to do with what they're driving. Keep the fuel prices high and a six-thousand pound SUV will cease to be Très Chic, if for no other reason than the social backlash.
Also, the current high cost of fuel is encouraging accelerated development in alternative fuel technologies, and that ain't a bad thing, errr, IMHO.
So, to sum it all up, keep the fuel costs high, and let folks drive what they want and as fast as they want to drive it.
Best Regards,
Shipo
Drilling the oil at our back doors, that maybe they will sell to us at inflated prices. :sick:
Kip
link title
Filled up for the first time last night.
374.6 @ 10.2 gallons = 36.7 mpg (not bad at all).
Alot of the driving was the trip back on 95 driving between 65-75 mph
interested to see what I get locally.
Usual 25 mile commutes sometimes @ 75 MPH and other times bumper to bumper traffic.32mph so far with these driving conditions seems fine to me.
CIVIC EX automatic gas using regular.
One increases the probability of less than optimum performance (over the life of the vehicle) if the vehicle is not properly broken in. Of course if the car is leased or you do not plan to keep it long, it doesn't matter much or is at worst, someone else's problem.