Honda Civic Hybrid

stevedebi · July 2004

Hopefully the on-line article was telling the truth about Toyota not allowing markups.

Honda dealers have a "dealer added price" sticker, where they basically say they are adding to the MSRP. I suppose it's allowed because they are listing the markup separately and openly. Different corporate culture, I guess...

misterme · July 2004

You are right, if a shopper is in the market for a low cost ride then the hybrid shouldn't be on the list.

Not sure about the 42mpg figure for the HCH but real owners are averaging about 47, Prius is just shy of 50, shown at the database of greenhybrid dot com.

One thing in particular I like about the HCH and I assume is the same with Prius, that it is a good candidate for hyper mileage if one takes the time to learn it.
It's nice to get more than 730 calculated miles out of 13 gallons of gas and some are doing even better than I am.
I'm not saying +60MPG tanks are normal for everyone: Most will get far less. But this high MPG is certainly achievable....for some.

Not sure of your highest risk of all (batteries). Mine is covered for 10 years/150K miles, about the time I'll be looking for my next car.

larsb · August 2004

I bought a used 2004 5-speed HCH earlier this month, had 4823 miles when I got it.

The previous owner had kept the "Trip B" odometer as the total miles on the car - the total miles and the Trip B odometer miles read the same number of miles.

Total MPG for the Trip B odometer reads 34.8 MPG. So to me, that logically says that the car has achieved only 34.8 MPG over the first 5700 miles.

Is that what I can assume? If so, that's pretty paltry overall mileage for a Hybrid, wouldn't you all agree?

Does anyone else have a trip meter that has been maintained equal to the mileage on the car, and does yours show something similarly low?

Thanks !!!

misterme · August 2004

35Mpg is really lousy for that car. Barring any mechanical defects the original driver must have been really hard on it.
That may explain the 35MPG and getting rid of it in 5,700miles.

Personally I use trip A for my daily commutes and trip B for tank to tank. For me, using one of the trip meters for lifetime mileage wouldn't work, as once in a while I'll accidentally reset it.

When I got the car in January I didn't know anything about driving with load and started off right away with mid 50's tank averages. By Feb-March I was upper 50's averages and I've posted my latest.

Since my driving habits are not "normal" please let me say that my wife occasionally uses the car, A/C full blast and knows little about conserving fuel, and she averages 45-50MPG on almost all of her trips.

If it were me I'd reset both trip meters, get the car up off the 30PSI tire pressure (if you haven't already...You be the judge here) and see what you can do for average tank MPG.

If you are still seeing the crummy 30's then I'd have the car checked, especially front end alignment.

larsb · August 2004

I agree on the lousy part..:)

My first two tanks have been 38.4 and 43.1, so I am doing OK with my two tanks I suppose. My driving is almost ALL city, very little highway miles, and I live in Phoenix, so I have been using the A/C almost full blast almost all the time. I have learned many good tips on these boards, and that's why my current tank is doing so well. Plus I have about 180 highway miles on that tank also.

My tires are 38 PSI. I'm using synthetic oil which I put in myself at 5073.1 miles. I use ECON and cruise control and I coast whenever possible.

I'm not going to get too awfully worried unless I start slipping into the 30s consistently. But I bought this car with the intent of getting low-to-mid 40s, so I hope I can do that.

Laters.......

stevedebi · August 2004

Slightly OT here, but I use Trip A for MPG, and Trip B for maintenance intervals.

PF_Flyer · August 2004

Be sure to check out our Town Hall chat lineup for Tuesdays... everyone is welcome and ALL things automotive (and some not-so-automotive topics) are fair game! Stop in tonight and get to know some of your fellow Town Hall residents better. We may even play a little automotive trivia!

Getting things started, from 6-7pm PT/9-10pm ET, If your passion is Mazda or you just like to go ZOOM ZOOM, the place to be is the Mazda Mania chat.

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larsb · August 2004

Notice in the C&D review that they mentioned that using the ECON on the Honda made a 13 MPG difference....That's seems high, no?

any comments?

misterme · August 2004

It would depend on how much time was spent while stopped.

econguy · August 2004

anybody out there replaced their HCH low rolling resistance tires?i've got a nail in the sidewall of a front tire, and am going to get both front ones replaced. i assume they're more expensive than normal, but just curious if anyone knows approx. cost and/or availability.

larsb · August 2004

Dear EconGuy:

TireRack.Com has the OEM tires for $67 each.....

Bridgestone B381 (Performance All-Season)
Specs | Warranty | Reviews
Sidewall Style: Blackwall
Size:185/70-14
SR Speed Rated Price: $67
Estimated Availability: In Stock

Hope this helps...Laterz.....

econguy · September 2004

before i post - thanks for the tire info, larsb...was very helpful.

the current problem i'm having cropped up in the past few weeks. i thought it would go away after i had the 40k maintenance done, but no such luck. when i'm driving under 5 mph - e.g. creeping along in stop and go traffic, or going through a parking lot - the car (which has a CVT transmission) is very "jerky". not a very technical term, i know, but it best describes what's happening. happens pretty consistently, regardless of whether i'm lightly stepping on the gas pedal, or taking my foot off of it and just letting the car coast along. motion is similar to driving a manual transmission, and not quite giving it enough gas before letting out the clutch - i.e. the car tends to lurch forward, albeit slowly in my case.

anybody at all have any clue or guess as to what the heck's happening? would appreciate any info, or even knowing if any other owner has had this experience.

thanks guys (and gals!)

john1701a · September 2004

> anybody at all have any clue or guess as to what the heck's happening?

Yup! The belt is slipping. Some owners have found relief by simply just getting the transmission fluid replaced. Try that.

Honda is having troubles with their CVT currently. GM had actually stopped production of their CVT in January. But they ended up resolving the problem. And Ford is debuting 2 vehicles with CVT for the 2005 model year. So it's likely Honda has some tweaking to do still.

Note that Prius uses a totally different CVT, the "planetary" type instead of a belt.

JOHN

misterme · September 2004

"Yup! The belt is slipping"
I've never came across any articles, technical or otherwise to support a theory of CVT belts slipping but would be interested in any links you may provide.

"Some owners"
Who were those owners?
I'd hate to hear of someone having the expense of a fluid change based on such a vague statement.

"Honda is having troubles with their CVT currently"
Again,
I've never came across any articles, technical or otherwise to support any Honda CVT problems. Other than your vague statments can you provide links?

"So it's likely Honda has some tweaking to do still"
Are you saying that Ford and GM CVT's are the same as Honda?
What tweaking does Honda still have to do?

isellhondas · September 2004

Honda has been building CVT transmissions since 1996 and I have never, once heard of any such troubles.

xcel · September 2004

Hi Isellhondas:

___If you have the chance to look over the pdfs of the reliability test article below, you will see 3 failed CVTs. Suspiciously the 3 that failed were driven by Bank One employees. I suspect they had an employee running full brake powered launches or some other such stupidity late in the life of these abused hybrids :-(

___You can see the entire list of results at the following: http://avt.inel.gov/hev.html

HCH pdf #3: 2003 HCH w/ CVT. Driven by Bank Ones courier pool. CVT and CAT failed at the 96 and 97K mark respectively.

HCH pdf #4: 2003 HCH w/ CVT. Driven by Bank Ones courier pool. CVT and CAT failed at the 99 and 100K mark respectively.

Insight pdf #3: 2001 Insight CVT. Driven by Bank Ones courier pool. CVT failed at 89K.

___Good Luck

___Wayne R. Gerdes

lngtonge18 · September 2004

There was a few owners mentioning CVT slippage on the Civic HX forum back in 2000 or so. I'm sure there have been improvements since then, but maybe that's where he got the impression that Honda was having problems.

larsb · September 2004

quote Stevedebi-"You are trading a sunroof and a fold down rear seat for 12-15 extra miles per gallon and the "climate control system" which is standard on the HCH and not available on the EX." Of course, the HCH has a lower engine oil change schedule, if I remember? Severe useage oil change schedule (double for normal useage): HCH - 3750 miles Civic EX - 5000 miles-end quote"

Correct, but who most people over the age of 35 have decided on a personal schedule of when to change their oil and they use that.

In my case, I'm not going to change the oil in my HCH any more frequently than I would a "regular" Civic - I use arguably the best synthetic oil on the planet and I'll change every five to seven thousand miles, based on oil analysis.

Owner's manual oil change recommendations are a "general guide" that the car manufacturer must publish to protect themselves.

misterme · September 2004

2004 HCH manual says oil change every 10K under normal use and 5K for severe conditions.

stevedebi · September 2004

"2004 HCH manual says oil change every 10K under normal use and 5K for severe conditions. "

Thanks for posting that; some previous posts had indicated a different mileage interval due to the different engine.

accordguy1 · September 2004

Hello everyone...
I currently have a '97 accord se sedan.
I love it's peppy ride but I'm planning to get a new accord within a couple of years.
Here's my dilema:
4 cylinder accord has good mileage but sluggish with a heavy load
6 cylinder accord has bad mileage and the low torque seems kinda sluggish too
the new hybrid accord seems the like the "perfect" car with power and mileage but I'm concerned about the "new" technology:
1) I live up in Boston and I've heard that the batteries don't work as well in the cold.
2) Any premium $ for the hybrid I'd make up over the life since I'd keep it for 150-200K miles but
I've heard that the batteries would be expensive to replace?
Do any of you Civid Hybrid owners have any insight of my concerns? Thank you...

misterme · September 2004

"I live up in Boston and I've heard that the batteries don't work as well in the cold."

I know of a few hybrid owners in the Northern states that have no issues when the batteries are cold.

"Any premium $ for the hybrid I'd make up over the life since I'd keep it for 150-200K miles"

If you keep your cars that long (As I do) you should break about even at the end for the price premium. When gas prices sky rocket again the premium will look better.

Breaking even is not a bad thing though. You'll be driving one of the most technically advanced autos they make, likely with alot of extras, be saving fuel and filling up less often.

"I've heard that the batteries would be expensive to replace?"

I've heard that if you were to replace the entire battery pack it would cost around $1500.
However the pack consists of numerous "D" size NiMH batteries and there is speculation that they may be tested and replaced individually.

I have an extended warranty that covers the car 70K/7YR B2B and 150K/10YR on the battery.

rfruth · September 2004

Honda Civic Hybrid commercial with the kid at the school science fair

http://www2.kluge.net/Civic.mov

It's 2.2 MB in size.

paul12 · September 2004

I just wanted to get started by sending a message. Recently bought Civic Hybrid. Only 300 miles so far. It is a 2005. I have to admit it was more the technology than anything else that interested me. I'm sure it will be more economical than my old Pontiac! One big question I had before buying was expected price I would pay. I didn't have a lot of references. Here in Hawaii I paid 20200 plus my 99 Bonneville. I got an extended warranty through Geico insurance but after reading the previous messages I'm going to have to see if it covers the battery etc. The dealer suggested that here I should follow the "heavy use " maintenance schedule because of the weather. I'm not sure that's really necessary.
Thanks to everyone who's already posted. The info is helpful.

misterme · September 2004

"The dealer suggested that here I should follow the "heavy use " maintenance schedule because of the weather. I'm not sure that's really necessary."

My dealer tried that on me even though I don't even qualify on the books specified heavy use criteria.
Must be an easy way to double their service profit from us.
I'm following the service schedule that applies to me...the 10K cycle.

I don't know about Geico but my Honda extended covers to 100K/7yr B2B and 150K/10yr battery.

paul12 · September 2004

I called Honda of America and they said stick to the suggested maintenance schedule that applies. Our trips are definitely longer than 5 miles and the weather is not always 90 but the continuous warm weather may be a factor in deciding. Geico covers 100k/7yr B2B but that includes the battery. It costs $30(thirty)per year with a 250 deductible. The dealer wanted 1300 for the same warranty you selected. They just sent a letter reiterating their offer so its still open to me. When I read the other messages the concern about the transmissions caught my eye. I wonder if that was just the earlier models. Someone did mention problems "in the past".
At any rate its been 10 days with no visits to the gas station yet and heading into 400 miles. we run the air con constantly so I'm sure that's going to affect mileage.As I said before it will still be a lot better than what we're used to!
Anyone change their own oil and trans fluid? I've changed the oil on my old cars.Is this one that different? The only 0-20 oil I can find here is synthetic except of course from the dealer.

larsb · September 2004

I change my own oil in my 2004 manual tranny HCH. Synthetic is fine - I use a 0W-30 synthetic here in Phoenix.

I am going to change the tranny fluid myself too when the time comes. I might decide on GM SynchroMesh, it seems to be the best manual tranny fluid out there, from what I could find so far.

Congrats on your fine choice of a car and good luck !!

blueiedgod · September 2004

I change my own oil in my 2004 manual tranny HCH. Synthetic is fine - I use a 0W-30 synthetic here in Phoenix.

Mobil 1 is available in 0W-20, which is direct replacement for the 5W-20.

0W-30 may not be such a good idea.

I am going to change the tranny fluid myself too when the time comes. I might decide on GM SynchroMesh, it seems to be the best manual tranny fluid out there, from what I could find so far.

If the hybrid tranny is similar to non-hybrid, I would strongly suggest that you stick with Honda MTF fluid. Using non-Honda fluids in Honda trans will most definatley void the warranty, and will affect the way the tranny behaves.
Same is true with Auto tranny fluid. If Hybrid uses CVT fluid, this is the only fluid that should ever go into the tranny, nothing else.

Cost should not be an issue as the Honda MTF or CVT fluids are resonably priced for products that have no competition.

larsb · September 2004

0W-30 is good oil:

"Mobil 1 0W-30 is the most advanced performance synthetic engine oil designed to provide the cleaning power, wear protection and enhanced fuel economy performance."

Another oil site says:

"All three oils (0W-30, 5W-30 or 10W-30) are excellent motor oils and ANY one can be used in a vehicle which requires either a 0W-30, 5W-30 or 10W-30 oil as well as in several other engine applications including an engine which recommends a 5W- 20 oil. This leads to the next topic: many people also ask us if the 0W-30 is too thin a viscosity oil for high ambient temperature operation. The answer is absolutely not! Thicker viscosity oils are not always necessarily better since in addition to its' various engine lubrication functions, an oil must also effectively transfer heat. Only about 60% of an engines cooling is performed by the engine coolant, and only on the upper half of the engine. The remaining 40% of an engines cooling is performed mainly by the engine oil."

Yet another site:

"0W-30 flows up to seven times faster than conventional oils. Therefore, it provides superior protection for engine parts during cold start-ups. And it safeguards your engine when it's extremely hot. Plus, 0W-30 helps maintain low oil consumption and reduces wear on starters and batteries."

I can find more examples, but trust me on this: I have used 0W-30 in my last five vehicles since 1997, and it does a fine job. It doesn't evaporate, and it helps fuel economy by reducing friction.

paul12 · September 2004

Any comments on the 2005 owner manual stating the mechanic should change the trans fluid then run the car,then drain and repeat process three times. I doubt a dealer would really do this. Thanks for the input on the oil change.

larsb · September 2004

Sounds like those tranny flush services at the regular car shops would be good for that...I doubt a dealer would do that without using one of those machines that the AAMCO and Goodyear shops use.....

blueiedgod · September 2004

Mobil 1 Racing 0W-30
SAE Grade 0W-30
Viscosity, ASTM D 445
cSt @ 40ºC 56
cSt @ 100ºC 10.3
Viscosity Index, ASTM D 2270 175
Sulfated Ash, wt%, ASTM D 874 1.2
HTHS Viscosity, mPa·s @ 150ºC ASTM D 4683 2.99
Pour Point, ºC, ASTM D 97 -54
Flash Point, ºC, ASTM D 92 234
Density @15º C kg/l, ASTM D 4052 0.851

Mobil 1 0W-20

SAE Grade 0W-20
Viscosity, ASTM D 445
cSt @ 40º C 43
cSt @ 100º C 8.4
Viscosity Index, ASTM D 2270 165
Sulfated Ash, wt%, ASTM D 874 1.28
HTHS Viscosity, mPa·s @ 150º C ASTM D 4683 2.61
Pour Point, ºC, ASTM D 97 -57
Flash Point, ºC, ASTM D 92 232
Density @15º C kg/l, ASTM D 4052 0.855

The differences are almost negligible, but I still use 0W-20. Exxon does not list viscosity at 0C, but if you look at difference in viscosity for 0W-30 and 0W-20 from 40C to 100C. I can imagine that 0W-30 is more viscous at sub freezing conditions. You can see that by the lower pouring point of 0W-20 vs. 0W-30.

But, all in all, any synth is better than dyno oil.

mauto · September 2004

Just some advice about calculating fuel economy using the fill-up method.

The 7th gen Civic's fuel tank is shaped such that it is highly variable as to when you have actually filled the tank. I know this because on occasion I've put more gas in my Civic than the 13.2 Gal capacity and driven for 50 more miles before the guage moves off "F". Sometimes I know the tank isn't quite full despite the pump's auto shut off kicking in. You shouldn't manually fill the tank once the pump shuts off to avoid draining into the emissions system. Why is this importatnt to know? Because when you only drive 100 miles and then refill, your mpg could be way off depending on when the pump shuts off.

Solution:

Use at least 10 tankfuls of gas returning to the exact same pump every time. Calculate your mpg each time and average all 10 readings to arrive at a reasonably accurate number.

It's possible to fill-up, drive 50 miles, fill-up again and the pump shuts off after only half a gallon added (pump shut-off calibrations differ at different pumps) and calculate your mpg to be 100. Of couse 100 mpg is impossible.

larsb · September 2004

Most of those variances are mis-calibrated gas pumps. 13.2 tanks are 13.2 tanks, regardless of tank "shape."

I've owned 12 cars in the last 25 years, and I have only once ever put more fuel than the tank was rated for, and that was only 0.1 more.....

xcel · September 2004

Hi Larsb:

___I have owned 12 vehicles in the last 10 years and all have been able to be filled beyond specified capacity. Currently, the Corolla will hold > 15, the Insight > 14, and the MDX > 22.

___Good Luck

___Wayne R. Gerdes

larsb · September 2004

Wayne, so you are TOPPING OFF your tanks? You know that is a naughty thing to do....:)

I know for sure that the following cars did not hold more than their rated tank capacities, because in these cars I *HAVE* topped them off and tried to shove every ounce of gas I could in them before learning the evils of topping:

2001 Avalanche
2000 Tacoma
1997 Suburban
1998 CR-V
1996 Camry
1994 Maxima
1993 Q45
1992 Cressida
1990 Cressida
1987 Maxima
1984 Maxima

My 12th car is the 2004 HCH, which I have not been able to put more than 12.5 in so far.

xcel · September 2004

Hi Larsb:

Wayne, so you are TOPPING OFF your tanks? You know that is a naughty thing to do....:)

___Yes, I top off all my tanks and have been doing so for over 25 years. I have never been scolded for doing anything naughty in regards to fuel fillups however ;-) With that, I have probably saved a few hundred gallons of fuel over the last 800,000 miles by not having to drive to the gas station and back nearly as often.

___Your evils are mistaken

___I cannot speak of the entire list of automobiles you posted but your HCH is either a ULEV or PZEV. If it is a ULEV, you most certainly can fill it up with more then 12.5 gallons. What you are probably not taking into account is that you never drive any of them to low enough fuel to place the rated capacity of the tank in them.

___Good Luck

___Wayne R. Gerdes

larsb · September 2004

Wayne, I stopped topping after doing a little research on the subject - check it out yourself and rid yourself of such an environmentally nasty habit which can also damage your catalytic converter.....even the EPA warns against it....

Yes, my HCH is a SULEV with a 13.2 gallon tank. I have yet to trust the gauge enough to drive it emptier....I will over time do so, however.

larsb · September 2004

some articles for why you shouldn't be topping off your gas tank (just stop at the first click!):
http://www.patgosscarworld.com/donttop.htm
http://www.phillyburbs.com/pb-dyn/news/113-06292004-323947.html
http://enviro2.blr.com/display.cfm/id/48985
http://www.sbcapcd.org/edu/dont-top-off.htm
http://www.weights.az.gov/Shoppers/gasstations.htm
http://www.viamagazine.com/top_stories/auto/how_bad99.asp

xcel · September 2004

Hi Larsb:

___First off, if your HCH is a SULEV, it is the PZEV version. That being said, you only have a 11.9 gallon capacity tank. With that and the fact you have placed 12.5 gallons in it leads me to the conclusion that you have already surpassed the capacity of your HCHs tank. The ULEV HCH on the other hand is a 13.2 gallon capacity tank.

___In regards to topping off, did you really think I havent read at least 100 more articles then the ones you have posted? How many times have I had problems? 0 in 800,000 miles. I dont dump fuel all over the side of my car either as it is to precious a commodity to do so. With that, guess how many times your drive to the station and pumping gas in poor climate has caused you to wish you werent sitting at the pump filling your tank? How many more trips to the gas station and back have you wasted fuel for no apparent reason anyway? You may as well just pour fuel out on the pavement and light it off each time you dont approach the actual range of your automobile less .2 to .4 gallons as it is such a waste to drive to the station and back needlessly which is what so many people do.

___I get the same stuff from those that think 50 #s in your tires is a bad practice as well. You know, when burst pressures are closer to 125  150 #s? Oh well, let us all close our eyes and keep wasting a precious commodity simply because it is the right thing to do. Blessed are those that dont have a clue as to what there present automobiles are truly capable of :-(

___Good Luck

___Wayne R. Gerdes

mauto · October 2004

Um, I think I started this whole fuel capacity debate so let me add this:

When Honda (and others) say the Civic tank is 13.2 Gal, they probably don't mean that it's 13.2 if you fill it all the way up the fuel filler pipe until it pours out the hole. It's probably somewhere below that quantity. Therefore it seems that you can always squeeze more in (though you shouldn't).

My original message had more to do with pump shut-off variances which directly affect MPG calculations. I've read numerous accounts of people getting 35mpg on one tank and then, miraculously, 50mpg on the next. This is not because the car found some new untapped efficiency, but because the 50mpg reading was calculated by a not quite refil of the tank - probably the pump shut off early and the driver thought, hey, 50 mpg!

greencars · October 2004

The Department of Energy completed a million miles of hybrid testing and found that the four Honda Civic Hybrids they were running averaged 38.0 mpg over a collective 284,000 miles. Six Honda Insights averaged 46 mpg over 347,000 miles, while six first-generation 2002-2003 Prius sedans averaged 41.1 mpg over 380,000 miles. A single 2004 Prius driven 16,000 miles was returning 44.6 mpg. The testing program is managed by the Idaho National Engineering and Environmental Laboratory, so it's credible.

larsb · October 2004

quote-"With that, guess how many times your drive to the station and pumping gas in poor climate has caused you to wish you werent sitting at the pump filling your tank?"-end quote

Firstly, regardless of if you drive to the pump every single day, you are not driving less or more than if you drive to the pump once a month, because you can only get mileage out of the gas in your tank no matter where or from you are driving. In other words, you can't drive more or less miles on more or less gas regardless. No matter when you fill your tank, 700 miles is 700 miles. If 8 of those miles was driving back and forth to the gas station, it matters not - 8 miles driven is 8 miles driven whether or not you are in Kalamazoo or Moscow.

If it is YOUR CHOICE to drive fewer times to the gas station and top off, just don't be under the assumption that you are immune to the harmful effects of topping off, because you certainly are NOT.

So it does not matter one whittle whether you fill your tank 18 times a year or 48 times - you still drive the same amount of miles and use the fuel you use before you need gas - filling up more or less often does not "cost" more gas - but what it DOES DO, if you top off, is all the harmful things that you know topping off can do. Good for you that none of your cars have suffered damage - but it's not an Urban Myth that such damage can and does occur. So harming the environment and your car by topping off does not make sense no matter how you slice it, or even even if you have driven 8
MILLION miles.

And as far as my tank capacity, I will check to see for sure what version of the car I have, but I'm darn near sure my tank is 13.2 gallons. And I know full well tank capacities are a "manufacturer's estimate" and that there are variations. But I can assure you there is no way I put 12.5 gallons into a tank rated for 11.9.....I'll get confirmation of my tank capacity later today, but my owner's manual says 13.2......

larsb · October 2004

"** 2004 Civic Hybrid models distributed in California, New York, Vermont, Maine and Massachusetts meet Advanced Technology Partial Zero Emission Vehicle (AT-PZEV) standards."

I bought mine in Arizona. The AT-PZEV model is 11.9 capacity, ULEV is 13.2

blueiedgod · October 2004

Solution:

Use at least 10 tankfuls of gas returning to the exact same pump every time. Calculate your mpg each time and average all 10 readings to arrive at a reasonably accurate number.

It's possible to fill-up, drive 50 miles, fill-up again and the pump shuts off after only half a gallon added (pump shut-off calibrations differ at different pumps) and calculate your mpg to be 100. Of couse 100 mpg is impossible.

I agree about filling up at the same pump every time, and as close as possible to "empty" but what about temperature? Fuel is measured in volume and not mass. If you fill up in the early morning when temperature is 50°F (10°C or 296°K not sure on the conversion) and then then next time you fill up at 4 pm when temperature is 80°F (26.7°C or 312.7°K) the volume will be different.

larsb · October 2004

You are absolutely correct - by filling up in cooler weather you do yourself a favor....

gagrice · October 2004

I agree about filling up at the same pump every time, and as close as possible to "empty"

I disagree with letting your tank get below 1/4 full. There is water and sediment that collects in the bottom of a gas tank and you don't want to pump that into your filter & injectors. Cutting yourself to the very last gallon to set some kind of worthless record is foolish. What happens if you are stuck in a snowstorm and require that fuel to keep warm. It is a false economy to run the tank down to the last little bit.

blueiedgod · October 2004

There is water and sediment that collects in the bottom of a gas tank and you don't want to pump that into your filter & injectors.

You are absolutley correct, water is havier than gasoline and will be at the bottom of the tank regardless if it is empty or not And whether you like it or not, the fuel pick up is at the lowest point of your fuel tank.

What happens if you are stuck in a snowstorm and require that fuel to keep warm
No one said to do those experiments in blizzard. Snow, slush and other wintry road conditions will decrease your mileage anyway due to increased resistance.

misterme · October 2004

It seems to me that in order to get the most accurate MPG reading one would need to:

1. Do an analysis on the fuel to ensure standard quality.
2. Begin by using compressed air or similar to blow the remaining fuel from the lines and injector. How much left over fuel can these contain? A pint or so?
3. Measure a single gallon of fuel using a newly calibrated meter or container (Not the gas pump) before dispensing into the tank.
4. Drive until out of fuel.

Other than that how can we get a true MPG reading with so many variables?

I'm not sure how practical that would be.
I have 2 main stations where I get fuel from.

I just pull up and fill until it clicks off and take the readings. Is that too practical?
Folks have been doing that since the gravity gas pumps were replaced in the 1930's - 40's?

larsb · October 2004

As these previous posts would indicate, it seems that at best, trying to pinpoint actual MPG is an Art rather than a Science, if not an exercise in futility.

I think anytime you are within 3-5 MPG of reality you are close enough.......

Honda Civic Hybrid

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