CALCULATING ACTUAL MPG
 

Hello everyone, I am new to this forum. Before joining this forum, I searched around the net, trying to find out at what fuel level (gallon(s) remaining) does the fuel low indicator light come on. I drive a brand new 2007 4Dr Honda Accord SE 4cyl Automatic. The owner's maunal says that the tank holds about 17.04 gallons but I can't tell if there is a reserve tank as well. The reason why I wanted to know this information is because I don't seem to be getting the outstanding gas mileage that is advertised for this vehicle. Example: if the fuel low indicator light kicks in at about 2 gallons remaining in the tank, then I am only averaging about 360 miles on 15 gallons, which comes to about 24mpg. If it kicks in at 3 gallons, then I getting about 25.71mpg.

I don't use the air conditioning much and my car is empty of any clutter that might weigh it down. I myself only weigh 165lbs. I do not drive aggressively and my commute to and from work is such that I am able to avoid peak rush hour traffic. I figure I should be getting at least 30mpg on average. Can anybody tell me what's the best way to figure out my actual gas mileage?

Thank you,

QC.

RE: CALCULATING ACTUAL MPG
 

Your method is faulty. The only way to estimate mpg is to fill up the tank completely, drive the car, and refill to the same level. Divide the gallons used into the miles driven.

Forget what the needle says or when the light comes on they have no bearing on figuring miles per gallon. By the way I think it's around 2.5 gallons when the low fuel light comes on.

RE: CALCULATING ACTUAL MPG
 

Thank you for your prompt feedback RTexasF. I will try your method and try to get an average over several fill ups.

-QC.

RE: CALCULATING ACTUAL MPG
 

You'll do well to average several tankfuls, like you say. Just the amount that's in the tank filler neck can throw it off.

The other thing is how new your car is. The mpg should go up a notch once things loosen up. If your commute is mostly city miles, I'd say you're doing good at 25 or 26.

RE: CALCULATING ACTUAL MPG
 

FWIW the fuel milage ratings are a BOGUS deal.
They set the car on a set of rollers and run it at different speeds; not really what you'd call Real World Conditions now is it?

RE: CALCULATING ACTUAL MPG
 

Yea, I read recently that the EPA is going to make car manufactures report their mileage capabilities in actual real world situations. I have never seen a car get what they advertise on the sticker. Especially when the engine is new. When the break-in period is over it should do better.

RE: CALCULATING ACTUAL MPG
 

To be fair, they have to use controlled tests to measure mileage. If not, then some poor car company will get theirs measured on a really really cold day, another on a really hot day.

The mileage depends way too strongly on your driving habits and climate & terrain. I usually get about equal to the EPA ratings.

RE: CALCULATING ACTUAL MPG
 

Thanks for all your feedback, everyone. Just an update: I know that the method I was using is inaccurate but when I wrote my first post last night, the tank was almost empty and I had estimated that the low level indicator light would kick in at 360 miles based on what the current trip log was at. It actually kicked in at 348 miles when I got to work. 348 miles on a full tank of gas? By my method and going by a 2.5 gallon minimum, that's only 23.93. Ugh... Hopefully, the other method will give me better results.

QC

RE: CALCULATING ACTUAL MPG
 

this is how I do it

pull into gas station
select pump I want and pull up to it
take note of milage on trip odometer
turn car off
fill tank with gas to 1st click
divide trip odometer milage by #of gallons indicated by pump
get in car
start car
reset trip odometer
drive off

the CL type S

194.5 miles on 7.48gallons = 26 mpg for mixed driving.....not bad for 300hp and 3.2L of monster V6 :P

RE: CALCULATING ACTUAL MPG
 

The other thing to keep in mind is that ALL the car mfgs know extremely well how to optimize their cars for the most mpg and lowest emissons in the govt tests, regardless of whether the tests accurately represent normal driving. Marketing 101.