I have tried to stick with Chevron gas, Regular. Curious if another brand will make a difference.
I have to admit, I take it pretty easy driving these days, now the first year or two with my new 97 Prelude was a different thing, wasn't too concerned with mileage back then...
Gotta admit they're just for looks on the EX with auto....
hey thats cool, those wheels look great, and the bigger rim/wider tire combo certainly helps you handle much better than the touring all season 205's on the stock wheels!
A car that handles good and gets good mileage is a great combo imo.
I've read the same thing. I will say I have had no problems filling to the brim for the last 4 years. I had a 2001 Honda Civic EX and I wanted to get an accurate mileage figure so I just filled it up slowly. Did that for 2 years and traded it in for a 2005 Pilot for my wife and have been doing it for almost 2 years now (104 fill-ups). The Pilot neck will take about 5 gallons - depending on temp & gas station pump. 24.980 gallons is my best on that car. (averages 19.23 mpg overall) As to my Civic, I have a 2003 LX with 120,553 miles last time I got gas - 287 tanks of gas - average MPG is 36.126 - median gallons filled is 12.932 - most gallons ever filed is 15.036 (manual says the tank is 13.2 gallons with 2 gallons in the neck, that was too close for comfort) - longest trip on 1 tank is 562 miles - median mileage between fill-ups is 463 miles - a couple of notes - typically I fill up when I leave the house - want to use the gas in the neck (in my Civic it will take 2 to 2.5 gallons after the pumps shuts down the 1st time) ASAP - not all gas pumps will allow you to do this, typically the older the pump the easier it is to fill it. It takes time - drives my wife crazy waiting for me, so I usually don't do it with her - You have to be careful obviously... I have had zero problems with my Honda regarding the way I fill the tank - as to that I have never had a problem with any of my Hondas - 93 Civic VX ran 275K, the 2001 Civic EX had 125K, my current 2003 Civic LX has 120K, and my wife's 2005 Pilot has 37K. PS - I made and keep excel spreadsheets for both cars.
too much fretting is more of a bother than a statistical benefit. A better way is to keep track over long periods of time so that the variabilities of the "click" even out statistically. But actually the click is a pretty reliable indicator. Use it.
Realize that gasoline stored in underground tanks is probably at about 65 degrees anywhere in the world. In your tank, surrounded by 95 degree air, it expands. 15 gallons at 65 degrees expands by about a quart at 95 degrees. That's enough to ruin a charcoal canister. Yeah, the 1st click is probably set conservatively (I can put almost 3 gallons in my wife's Highlander after the click), but don't push it to the infinite degree. It isn't worth the risk and it does no good.
After all, tracking mileage is really only good for bragging rights and to spot trends. And to spot trends, you need long term data. Comparing a single tank to another is pointless unless there are specific items you are looking for (recent repair, 2 very different trips/driving styles, etc).
My method is to simply fill until it shuts off the first time, then go until I reach the next even $$ amount. I like nice round numbers! Does the amount of the fill vary? Sure, but over time, it is immaterial. At $3/g, rounding up to the next whole $ at most adds 0.3 gallons, well within any long term statistical variance.
And yes, I too keep a spreadsheet. It's my inner geek...
If it clicks at $10.01, and since I like to round the $ to the nearest whole dollar, I pump until it reaches $11.00.
At $3/g, that adds $0.99 or 1/3 gallon. WIth this method, $0.99 is the most you will ever add beyond the 1st click. At higher $/g, the amount added will be even less (at $4/g, it would be .25g, $5/g would be .20g, etc...)
On my last fillup, had I stopped at 1/3 gallon less, my 1-tank MPG would have been .6 better.
In the longterm, .6 MPG is statistically insignificant. And 1/3g extra will not hurt anything.
How can adding more gas improve the MPG? The mind boggles...
You reset the trip computer, then drive around. When you re-fill, you divide the number of miles by the number of gallons _you just put in_ and you get the MPG for the _last_ fill-up.
For true! The only thing filling up the neck of the fuel tank does is extend RANGE. All things being equal, 12 gals will go further than 10 gals. The problem also with "necking it up" is when you are motoring along in 110 degrees, you still need app expansion room. So if you are "necking up" you better not shut down until you do have the right expansion room.
While it was not my quote, the logic you use in message # 718 is the reason why one should do it consistently (I use the first click off, per your message #718). But which ever way one does chose, the real goal is ACCURACY over time, fillings, miles, etc, SEE?
my point is that over time, the 1/3 g is statistically insignificant.
simply put, +/-.5mpg is of no concern when looking for trends, issues and other reasons for tracking mileage in teh real world.
If you study the entire system, you will see that there are other variables that contribute larger variances, like "click" consistency between pumps, rate of flow (affects click timing), etc.
Yes, accuracy is of concern, but you have to know when accuracy is useful.
On the 1/3 of a gal point. It does make a difference. So say I get 39 mpg and use 10 gals or 390 miles. Now I use 10.3 gals in 390 miles, the mpg is now 37.86 mpg. or almost 3%.
A plus or minus non consistent fill IS!! Which is my point and which you are trying to ignore.
Okay, you guys are both right. If you only were measuring mpg based on one fillup, then 1/3 of a gallon is significant. On the other hand, if you keep track of all of your fillups and you fill it up 10 times, using 100 gals of gas and having driven 3900 miles, then the last 1/3 gal potential error would be insignifcant at .3%
You'll have a larger error on your odometer reading mileage than .3%, if you've ever checked it with a GPS.
Actually what you are saying is true. It was surprising especially in light of the bru ha ha from a recently settled Honda lawsuit (inaccurate odometer) Since I do use a GPS, I was surprised to see it pretty much dead on. (triangulated so to speak) As you know, you don't really NEED a GPS, as there are some stretchs of road that have mile signs, that you can further check this against (mile 0,1,2,3,) and normal highway signs that give destination/s distance/s.
Yes you could do it on highway mile signs, but if you use a GPS you can track it for a much longer distance...thereby reducing any tracking error to neglible.
"And evidently someone else who does not understand what consistency entails. "
"All things being equal, 12 gals will go further than 10 gals."
And someone who doesn't read for comprehension/understanding.
I agreed with your first click procedure, and I fully understand that you round UP higher for accounting purposes, i.e., you like round $ numbers. I don't round up. Either is no big deal.
"But actually the click is a pretty reliable indicator. Use it. "
some messages back, but more importantly, explained why. I also have IE in my background. So yes, let's move on.
I just got 29.6 MPG at my latest fill-up. I've been averaging right about 28. The latest included one ~50 mile highway trip... otherwise it was just my average weekday driving. Uninterrupted highway driving -- even on such a short trip -- seems to make a more noticable difference in this car than anything I've owned before.
I have an 04 Civic Ex. All of my driving is in the Chicagoland suburbs. I just got 35.6 MPG, which is pretty much what I usually get - I drive pretty smoothly. I calculate my MPG by tracking my mileage and always pumping at the same (local, no-name) gas station and always the same pump, set on slow, until the frist click.
My highest MPG ever was 39.0, with about 60% highway 40% suburbs.
I've read about a guy who got 59MPG in his new Accord (non hybrid)- crazy. :surprise:
averaging 29mpg for intown, consisting of idling in heavy traffic and bursts to 80-85mpg at times, maybe 1/2 without AC. Averaged over 6-7 tanks. Life in the Big City.
A SINGLE tank on a weekend trip, mostly highway, cruise control (at 72-75 depending on traffic) as much as possible and AC: 33mpg. I would consider this about the best driving conditions I will ever see for "highway" mileage, so we filled it shortly after arriving to get the purest highway results without much "city" driving in the mix.
includes extra wide tires (215/40/18) which don't help mileage.
Since the warmer weather my 06 civic has been getting somewhat better MPG. I was avg 26 mpg now I am avg 28 mpg driving the same route. Does the warmer weather effect mpg?
actually warmer weather should hurt mileage as the air is less dense and contains less oxygen. You may be seeing a difference based on a seasonal change in gasoline/ethanol blend which varies by region. Less ethanol means better mileage.
Also your tires will run a bit hotter making the air expand a bit more; more tire pressure can improve mileage.
You may be warming up the car less than you did in colder weather, idling eats mileage.
hey, i have a 95 civi cex, coupe, i used to get about 41mpg stock, then had it street tuned on crome pro software, got aruond 45mpg..... then i turbod it, now i get about 15-20mpg....lol sucks
The colder/higher density air of the winter months will allow you to get more power from your engine, however, since fuel doesn't atomize as well with a cold intake charge, your mileage will suffer.
The warmer/lower density air of the summer months will reduce max power (sometimes dramatically so if high humidity is involved as well), however, because fuel so readily atomizes with a hot intake charge, there will be far fewer "rich zones" in the combustion chamber, allowing for more power to be derived from what air and fuel does make it to the combustion chamber.
So, if a hot intake charge yields more power from any given unit of gasoline, why don't you get more power from your engine in the summer time? Simple, your engine measures the weight of the air entering the engine, and then provides a given amount of fuel for every pound of air (typically something a bit over stoichiometric which is roughly 14.9 weight units of air to 1 weight unit of fuel). Since lighter air is entering the engine in hot weather, less fuel is pumped in via the fuel injectors, and so even though you're getting more power per unit of fuel, the max power of the engine is reduced.
...thats why I said "should". It varys a lot, and realistically other factors tend to impact it more. In most cases the differences in winter-vs-summer mileage can be placed squarely on ethanol (as in "winter" and "summer" blends).
Ethanol is never good for mileage OR power.
But since your intake has a heater (many if not most cars have a tube from the cooling system going into the intake to heat the air for emissions purposes, addressing the atomization issue you mentioned), the cold air isn't cold enough once it gets to the cylinder to have that kind of negative effect.
However, the oxygen content is a bit higher in colder months (depends on location and other things, but usually is so), and even if warmed/expanded a bit in the intake, the o2% tends to stay higher, and that makes the difference.
Altho as you said, it should be minimal, especially when compared to larger factors such as driving habits and ethanol.
"But since your intake has a heater (many if not most cars have a tube from the cooling system going into the intake to heat the air for emissions purposes, addressing the atomization issue you mentioned), the cold air isn't cold enough once it gets to the cylinder to have that kind of negative effect."
Uhhh, I've been elbow deep into LOTS of engines over the decades, and I don't think I've ever seen a single engine that used coolant to warm the intake charge. As such, I'm going to have to call you on that one, please provide references to support your clam.
In the meantime I stand by my statement; the single most significant reason why fuel economy suffers in cold weather is because the fuel cannot atomize as well as it can in the summer.
FWIW, there was a time before fuel injection became the norm when many carbureted engines used a vacuum controlled diverter in the air-cleaner horn to route intake air from around the exhaust manifold, however, IIRC, such systems deactivated once the engine was warmed up.
FWIW #2: To this day, carbureted IC aircraft engines allow the pilot to select "Carb Heat" by pulling a knob out of the panel that gradually switches the intake path from cold air to exhaust manifold heated air. That system is in place so that the pilot can melt any accumulated "Carb Ice" down stream of the venturi(s). More recently it has been widely published that some pilots are also using partial carb heat to aid in mixture distribution when flying in an area with an OAT below roughly forty degrees.
Dude, I'm afraid you're going to have to do better than the above two oblique references.
Regarding your Camry, I'd warrant that the intake charge gets no intentional or meaningful heat exchanged from the way the coolant is routed.
Regarding SwRI, I've combed their online articles and have been unable to come up with even a single one that supports your arguments.
I suggest that if you want to continue this exchange, you provide some concrete references to support your assertions. In the meantime I will just assume that you've been misinformed about how engines operate.
As it applies to MPG there is a surprising large amount of "mis" information about air intakes for specifically Honda Civic's. But in a manner of speaking there is really no surprise as to why. With mineral oil selling at over 80 dollars per gal and air intakes' between $45 and WAY on up, there is a good fight for the hearts and minds....
This Civic is my wifes car. She convinced me to take it instead of my Buick SUV because of gas prices. I can't get used to the responsive steering. My Buick floats and the Civic doesn't take much on the steering wheel to be in the next lane.
Civic LX sedan 1.8A-- First tank was 20mpg. Since then I am averaging 24 to 25. I am on my 5th tank now. And I bought this for the 30\40 mpg claim. Too bad I got rid of my 15 yr old reliable compact that gave me 24 mpg for the same city drive I do day in and day out - for a "Honda" name and current technology.
Those in the market be careful. For those who get what Honda claims consider yourself lucky. Looks like mine runs on "Lemon" juice.
I have been following this thread for a while. Has anyone who has suspected something wrong with the car- affecting fuel mileage mpg, brought it to the dealer and/or independent to have it diagnosed? If so, what were the results?
Another person who thought the EPA "estimate" was a given. Too bad consumers aren't educated by the selling dealer before they drive off the lot with their 30 city-40 highway Civic. For your information the EPA sticker (up to the 2006/7 model year) is a U.S. government mandated bit of mis-information that is derived from a bogus, outdated test. The latest EPA sticker for the Civic (and others)has been heavily modified to show a more realistic set of city/highway numbers and has been reduced to something like 25 city 35 highway (not necessarily the exact numbers). I also get 23-25 mpg in suburban driving and 36 highway. These are more in line now with the latest and greatest from the EPA.
Too bad consumers aren't educated by the selling dealer before they drive off the lot with their 30 city-40 highway Civic.
Who are you kidding? No dealer with even half a brain is going to tell customers the car won't do what the sticker says. AMOF, I asked the salesman what others were getting in their Civics. He told me that some have gotten better than the EPA estimates, although "some" could be as few as two.
So far my 07 Civic EX with AT is getting around 30 mpg in local driving. But my car still has less than 1500 miles on it, so it's hard to know for sure how it will do. Give me to 5000 miles and I think I'll have a pretty good idea.
I talked to a guy a few days ago who commutes from a neighboring town every day. It's about a 60 mile round trip. He said he's been getting 34-36 mpg depending on how much running around he does in addition to commuting to work.
I will also go on the record with this: If I bought any car and it was averaging 5 mpg less than the estimated city mileage, the service manager and I would be having a meeting of the minds. I know those numbers are estimates, but I've also had cars that did better than the estimates, and I've never had a vehicle that consistently got worse than the city mileage.
Comments
I have tried to stick with Chevron gas, Regular. Curious if another brand will make a difference.
I have to admit, I take it pretty easy driving these days, now the first year or two with my new 97 Prelude was a different thing, wasn't too concerned with mileage back then...
hey thats cool, those wheels look great, and the bigger rim/wider tire combo certainly helps you handle much better than the touring all season 205's on the stock wheels!
A car that handles good and gets good mileage is a great combo imo.
Realize that gasoline stored in underground tanks is probably at about 65 degrees anywhere in the world. In your tank, surrounded by 95 degree air, it expands. 15 gallons at 65 degrees expands by about a quart at 95 degrees. That's enough to ruin a charcoal canister. Yeah, the 1st click is probably set conservatively (I can put almost 3 gallons in my wife's Highlander after the click), but don't push it to the infinite degree. It isn't worth the risk and it does no good.
After all, tracking mileage is really only good for bragging rights and to spot trends. And to spot trends, you need long term data. Comparing a single tank to another is pointless unless there are specific items you are looking for (recent repair, 2 very different trips/driving styles, etc).
My method is to simply fill until it shuts off the first time, then go until I reach the next even $$ amount. I like nice round numbers! Does the amount of the fill vary? Sure, but over time, it is immaterial. At $3/g, rounding up to the next whole $ at most adds 0.3 gallons, well within any long term statistical variance.
And yes, I too keep a spreadsheet. It's my inner geek...
If it clicks at $10.01, and since I like to round the $ to the nearest whole dollar, I pump until it reaches $11.00.
At $3/g, that adds $0.99 or 1/3 gallon. WIth this method, $0.99 is the most you will ever add beyond the 1st click. At higher $/g, the amount added will be even less (at $4/g, it would be .25g, $5/g would be .20g, etc...)
On my last fillup, had I stopped at 1/3 gallon less, my 1-tank MPG would have been .6 better.
In the longterm, .6 MPG is statistically insignificant. And 1/3g extra will not hurt anything.
You reset the trip computer, then drive around. When you re-fill, you divide the number of miles by the number of gallons _you just put in_ and you get the MPG for the _last_ fill-up.
please re-read the post a bit more carefully. Stopping sooner at the 1stclick uses less gas.
perhaps I was not clear:
stopping at the first click gives x gallons used.
adding ~1/3 g after that 1st click gives x + 1/3 gallons used.
both are divided into the same number of miles.
another way:
300 miles / 10 gallons= 30 mpg
300 miles / 10.3 gallons = 29.12 mpg
see?
simply put, +/-.5mpg is of no concern when looking for trends, issues and other reasons for tracking mileage in teh real world.
If you study the entire system, you will see that there are other variables that contribute larger variances, like "click" consistency between pumps, rate of flow (affects click timing), etc.
Yes, accuracy is of concern, but you have to know when accuracy is useful.
A plus or minus non consistent fill IS!! Which is my point and which you are trying to ignore.
You'll have a larger error on your odometer reading mileage than .3%, if you've ever checked it with a GPS.
stopping at the first click gives x gallons used.
adding ~1/3 g after that 1st click gives x + 1/3 gallons used.
both are divided into the same number of miles."
Yes, you were clear, but not correct. Why do you divide into the same number of miles? If you put more gas, your car will go farther.
"another way:
300 miles / 10 gallons= 30 mpg
300 miles / 10.3 gallons = 29.12 mpg "
So if I fill only half the tank I get
300 miles / 5 gallons= 60 mpg ???
If you measure both miles and gas refilled between similar events (click-to-click or click plus 1-to-click plus 1) you should get comparable mileage.
????are you serious????
because you check mileage by how far YOU'VE ALREADY GONE, not for how far you "will" go.
And evidently someone else who does not understand what consistency entails.
If you want to argue credentials, I am an Industrial Engineer with 30+ years experience in Costing Analysis and such.
"All things being equal, 12 gals will go further than 10 gals."
And someone who doesn't read for comprehension/understanding.
I agreed with your first click procedure, and I fully understand that you round UP higher for accounting purposes, i.e., you like round $ numbers. I don't round up. Either is no big deal.
"But actually the click is a pretty reliable indicator. Use it. "
some messages back, but more importantly, explained why. I also have IE in my background.
poor poor honda civic! :sick:
I just got 29.6 MPG at my latest fill-up. I've been averaging right about 28. The latest included one ~50 mile highway trip... otherwise it was just my average weekday driving. Uninterrupted highway driving -- even on such a short trip -- seems to make a more noticable difference in this car than anything I've owned before.
I just got 35.6 MPG, which is pretty much what I usually get - I drive pretty smoothly. I calculate my MPG by tracking my mileage and always pumping at the same (local, no-name) gas station and always the same pump, set on slow, until the frist click.
My highest MPG ever was 39.0, with about 60% highway 40% suburbs.
I've read about a guy who got 59MPG in his new Accord (non hybrid)- crazy. :surprise:
http://www.motherjones.com/news/feature/2007/01/king_of_the_hypermilers.html
Just to let you know, such high mpg is not attainable in normal driving - you'll know what I mean once you read the article.
Driving is definately the key.
A SINGLE tank on a weekend trip, mostly highway, cruise control (at 72-75 depending on traffic) as much as possible and AC: 33mpg. I would consider this about the best driving conditions I will ever see for "highway" mileage, so we filled it shortly after arriving to get the purest highway results without much "city" driving in the mix.
includes extra wide tires (215/40/18) which don't help mileage.
just fwiw.
Your mileage may vary.
Also your tires will run a bit hotter making the air expand a bit more; more tire pressure can improve mileage.
You may be warming up the car less than you did in colder weather, idling eats mileage.
The colder/higher density air of the winter months will allow you to get more power from your engine, however, since fuel doesn't atomize as well with a cold intake charge, your mileage will suffer.
The warmer/lower density air of the summer months will reduce max power (sometimes dramatically so if high humidity is involved as well), however, because fuel so readily atomizes with a hot intake charge, there will be far fewer "rich zones" in the combustion chamber, allowing for more power to be derived from what air and fuel does make it to the combustion chamber.
So, if a hot intake charge yields more power from any given unit of gasoline, why don't you get more power from your engine in the summer time? Simple, your engine measures the weight of the air entering the engine, and then provides a given amount of fuel for every pound of air (typically something a bit over stoichiometric which is roughly 14.9 weight units of air to 1 weight unit of fuel). Since lighter air is entering the engine in hot weather, less fuel is pumped in via the fuel injectors, and so even though you're getting more power per unit of fuel, the max power of the engine is reduced.
Make sense?
Best Regards,
Shipo
Ethanol is never good for mileage OR power.
But since your intake has a heater (many if not most cars have a tube from the cooling system going into the intake to heat the air for emissions purposes, addressing the atomization issue you mentioned), the cold air isn't cold enough once it gets to the cylinder to have that kind of negative effect.
However, the oxygen content is a bit higher in colder months (depends on location and other things, but usually is so), and even if warmed/expanded a bit in the intake, the o2% tends to stay higher, and that makes the difference.
Altho as you said, it should be minimal, especially when compared to larger factors such as driving habits and ethanol.
Uhhh, I've been elbow deep into LOTS of engines over the decades, and I don't think I've ever seen a single engine that used coolant to warm the intake charge. As such, I'm going to have to call you on that one, please provide references to support your clam.
In the meantime I stand by my statement; the single most significant reason why fuel economy suffers in cold weather is because the fuel cannot atomize as well as it can in the summer.
FWIW, there was a time before fuel injection became the norm when many carbureted engines used a vacuum controlled diverter in the air-cleaner horn to route intake air from around the exhaust manifold, however, IIRC, such systems deactivated once the engine was warmed up.
FWIW #2: To this day, carbureted IC aircraft engines allow the pilot to select "Carb Heat" by pulling a knob out of the panel that gradually switches the intake path from cold air to exhaust manifold heated air. That system is in place so that the pilot can melt any accumulated "Carb Ice" down stream of the venturi(s). More recently it has been widely published that some pilots are also using partial carb heat to aid in mixture distribution when flying in an area with an OAT below roughly forty degrees.
Best Regards,
Shipo
It is often disconnected by street racers to keep the intake air that much cooler.
and fwiw, most of my info came from a former head of the automotive testing group at Southwest Research Institute.
Regarding your Camry, I'd warrant that the intake charge gets no intentional or meaningful heat exchanged from the way the coolant is routed.
Regarding SwRI, I've combed their online articles and have been unable to come up with even a single one that supports your arguments.
I suggest that if you want to continue this exchange, you provide some concrete references to support your assertions. In the meantime I will just assume that you've been misinformed about how engines operate.
Best Regards,
Shipo
Best Regards,
Shipo
Those in the market be careful. For those who get what Honda claims consider yourself lucky. Looks like mine runs on "Lemon" juice.
looks like you run on hot gas. (couldn't help it.
Could be your driving conditions, your driving style or something actually wrong with your car.
http://www.fueleconomy.gov/mpg/MPG.do?action=browseList2&make=Honda&model=Civic
Thank you.
Who are you kidding? No dealer with even half a brain is going to tell customers the car won't do what the sticker says. AMOF, I asked the salesman what others were getting in their Civics. He told me that some have gotten better than the EPA estimates, although "some" could be as few as two.
So far my 07 Civic EX with AT is getting around 30 mpg in local driving. But my car still has less than 1500 miles on it, so it's hard to know for sure how it will do. Give me to 5000 miles and I think I'll have a pretty good idea.
I talked to a guy a few days ago who commutes from a neighboring town every day. It's about a 60 mile round trip. He said he's been getting 34-36 mpg depending on how much running around he does in addition to commuting to work.
I will also go on the record with this: If I bought any car and it was averaging 5 mpg less than the estimated city mileage, the service manager and I would be having a meeting of the minds. I know those numbers are estimates, but I've also had cars that did better than the estimates, and I've never had a vehicle that consistently got worse than the city mileage.