SilverTSXinPA

Well I had to post this for you folks. I just made a round trip from Harrisburg, PA to Portsmouth, NH and got the best mileage yet. As some of you will know, this is rather hilly terrain. From Harrisburg to Portsmouth used cruise control, locked on 70 mph a/c off. Got 36.7 mpg!!! Coming back speeds 70-85 and got 32.6 mpg. Damn...this car just keeps amazing me!!!

tirebiter

That's pretty good.

I just drove from NYC to Dallas in 2 days, averaging 75-80 all the way. I tend drive on cruise control, except I speed up on hills (seems to be a safe place to avoid traps because most people slow down on hills).

I averaged 29MPG. Exactly what the EPA did.

MSM-5AT-Navi

Speed Demon

Over Thanksgiving weekend, I traveled from Dayton, OH to Washington, PA on I-70, and I got 36.1 mpg averaging a speed of 80 MPH! (Drove 240 miles in 3 hours). I was impressed to say the least.

rb1

Just curious as to how you guys are calculating mileage.

(IMHO the only "guaranteed" method is to fill up the car before and after the trip and divide the miles driven by the amount of the second fill up)

jlukja

That's my method too. I also make sure I don't "top off". Its full when the pump clicks off.

I would have posted my mileage also but I forgot to write down how many gallons I put in the last time.

SilverTSXinPA

Yep. That's how I did it. Been doing it that way for 30 years.

tirebiter

Yes, I use MPG = (Miles driven) / (Fillup volume)

dnl2ba

Yeah, the navigation system's estimate seems consistently optimistic.

jlukja

After my 2nd fill up tonite averaged 27mpg since I picked it up at the dealership with 3 miles on it. I'm not disapointed at all considering its still in the break-in phase and its been driven about 50/50 hwy/city. I would expect that to actually go up a little after a few 1000 miles.

dnl2ba

I've mentioned elsewhere as well: I haven't noticed a change in mileage over the 7800 or so miles I've driven my TSX.

Bass Mechanic

i got 33 MPG doing 84 MPH on a trip from nevada through arizona i use the Navi MPG estimates and if they are wrong i really dont give a crap. if it says 33 MPG ill go with it im not going to calculate the gas and miles the trip computer should do a fairly decent job of that.

TinkySD

I just got 28mpg on my weekend trip to LA for the autoshow. I'm very pleased considering that there were 3 in the car with AC on most of the time as well as in stop and go traffic for at least 1/3 of the total miles.

ABP-CL9-TSX

I've been averaging 21-22MPG in mines, but then again mines is a 6 speed and not a Auto TSX. I wish I got an automatic.

LeMasseHammer

No regrets on the 6MT here

I just filled up last night, and calculated 21.1 MPG. That may sound low, but as I've mentioned before, that's 90% city driving and I've been promoted to Supreme Commander of Planet Leadfoot. I pretty much decided that I wanted to see how low of an MPG I could get out of one tank, and this is it.

Maybe gas is just too cheap, enabling loons like me to behave this way

rb1

It seems like folks computing the actual gas mileage are coming up with numbers 10-20% less than the Navi numbers. Do you consider a 20% error to be decent? How would you feel if the gas station overcharged you by 20%, or (perhaps worse), you ran out of gas because you believed the "estimated miles to refill" number.

More to the point, folks beginning threads entitled "Amazing fuel economy" should provide reliable figures rather than Navi "estimates" IMHO...

SilverTSXinPA

As the originator of this thread, I just wanted to let you know that my mpg is based on actual not navi. I do not have navi in my TSX. Didn't mean for this to go into a "navi is not accurate" discussion. I only wanted to point out that 36.7 mpg out of this type of vehicle in hilly/mountanous terrain is remarkable and that I am quite pleased with my TSX.

rb1

Fair enough, but it would have been helpful if you, as the originator of the thread, had responded to my earlier question regarding how the mileage was being calculated.

SilverTSXinPA

I did, well perhaps not specifically, but, I do menion in a subsequent response that I have been calculating fuel economy "the old fashioned way" for quite a while. Anyhow, I would have been happy getting 28mpg on the highway, as I regularly get about 21 around town. Over 36 mpg was totally unexpected and over 32 when pushing it was just a little piece of icing on the cake.

rb1

Good grief, I'm getting blind in my old age. Mea culpa.

Bass Mechanic

ill try a tank one of these days and do a calculation and compare to the navi. i suspect 20% off is a little high. i know for a fact on long trips i have taken the fuel economy and distance to empty is fairly accurate. the average MPG people are using with the navi i would like to know if they used the data stored when you refill or if they went off of the average displayed while driving that tank. because i know for a fact the one that gets stored is always different than the one shown while driving. the stored figure is usually lower than the current MPG calculation.
now i dont know how the stored value is determined but i have a feeling it is total miles driven and the number of gallons used before the fillup.
the only way that figure could be off is if the system calculates the fuel used incorrectly. if that were the case than the distance to empty would be wrong while driving. in my experience it has been very accurate.

i am certain that the MPG displayed while driving is accurate while driving. i think the descrepency comes into play because i dont think the average MPG while driving is actually average for the whole tank. i belive it is average for the last X number of miles.
i say this because i have seen the economy go from 29 mpg driving 85MPH to 36 mpg while driving 65 MPH on the same tank and within 30 minutes of the first number. there is no way you can average 29 MPG and 20 mins of 36 mpg and get an average like that it would have to fall in between thoes 2 figures.

my 33 MPG was at 84 MPH was while driving for about 2 hours at that speed and that was displayed on the Trip Computer while driving. i belive this figure to be accurate for that portion of the fuel used but not for the whole tank.

ill be leaving on a trip to Kansas City MO on the 27th of this month. im leaving early in the morning and i know the trip is about 588 miles. that should be just a little over 1 tank full. i intend to drive near the speed limit the whole way without stopping and from the start using only minimal throttle to get up to speed. if i can start off my average at a high MPG and maintain that MPG along the trip this will proove a lot of theroys.
if the 2 MPG values match and match with calculated at the pump figures then it will proove if the system is off and why.

rb1

Yes, this makes sense. I thought the Navi-based numbers were coming via some "Your mileage since the last fillup was X" type statistic but since I don't have it it's hard to know.

My experience is that most cars can routinely exceed their highway EPA estimates by 10% or so with just reasonably conservative driving, so 32-33 mpg from the TSX doesn't surprise me at all. You can get somewhat more by driving 65 mph or less, drafting other cars, etc., but wild numbers (like 25+% above estimates for an entire tank) make me wonder about things like gas pump accuracy or incomplete fill (e.g. relying on the auto-stop, car not level when putting in gas), etc. I once filled up my old Integra at a gas station and put more than 15 gallons in it (per the pump). Trouble is, it only had a 13.2 gallon tank.

Dani

i got the 5AT TSX navi with everything unchaged except 12 lbs more than the factory TSX due to aftermarket tires + rims.

i always use my navi data as the reference for fuel consumption, somehow my MPG is extremely bad, always like 22-24 mpg something, i am assuming there's something wrong with my navi's calculating system...anyone ever got the same problem?

pretty sure my driving style deserves more MPG

jlukja

Just completed a roadtrip last weekend. Averaged 30.4mpg, first time I was able to get over 30mpg on a tank. I've been keeping track of the mileage and its been getting better as the engine breaks in. The first 1000 miles I averaged 26.4mpg but the last 900 miles I averaged 28.5mpg. At this rate I fully expect to average 33-34 highway mpg once the engine is fully broken in. Its a good thing too because 91 octane gas here in California is around $2.30/gal.

Mokos23

right now i'm avg 23-25 mpg city driving and prob 32-34 mpg on the highway. i know that keeping the air in your tires at 32 psi or higher will greatly help in obtaining better gas mileage.

my smartass friend told me to put my tires at least to 38-40 psi and i'll watch my gas mileage even go up further.....



maybe, but wouldn't i ruin my tires then if i put it to 40 psi?

ofc319

OK. Now I am really starting to think I have some kind of situation. I had started a "winter gas" thread awhile back to talk about my poor MPG.

I have a 5AT, my most recent trip, three adults in my car, highway speeds of no more than 70MPH, using cruise control... 22 MPG using the same method as everyone else.

Does anyone know if there is something that the dealer can check in my car, maybe the computer(?) to find out why my mileage sucks? I have yet to get above 23MPG for the last 3 months. In fact, I would say that my mileage has become worse since I have owned the car, not better.

In comparison to everyone else, you would think I am driving an H2.

jlukja

Based on your posts I definitely think you should take it to the dealer. It doesn't seem your driving habits are the cause. They should run a diagnostic to make sure your engine is running right. Also check the tire pressure, alignment, look for uneven wear on you tires and or unusual wear on you brakes. Either your engine is not operating at optimal setpoint or something else is causing unusually high roling resistance. Good Luck

ofc319

Thanks JLUKJA for your thoughts. I wrote it down and will have the dealer check these off in order with my next oil change. Luckily, I am traveling for the next month and will only drive the car for about 3 weeks until mid-April. I am hoping it is just a winter gas thing.

For the life of me I can't figure it out. Sure, sometimes I go like hell, but when I am concious of my speed and set the cruise, I expect more than the city figures.

Well, that's my only complaint. I have the boss paying for the car, now if I can swing the gas I will have nothing left to gripe about!

For those of you with the great mileage, I'm jealous. If you see me on the road don't expect me to keep up...I'm conserving fuel!