Poor MPG

[cmccarthy]

i have been keeping track manually with fuel mileage. about 99% city driving and around 13-14.5 mpg.

i dont look at the console with the read out.(it is not accurate at all)

usually it is ranging around 135-145 miles per half tank.

 

i dont have a heavy foot.

i am going for my first oil change. 3000miles on it.

 

i have the faith it will improve with time and miles.

 

 

The main problem with manually checking mileage is that you have no way of accurately determining that you have filled the tank to the exact same level as the last time you refuelled. Hence, mileage figures can be skewed considerably.

[bbf2530]

The main problem with manually checking mileage is that you have no way of accurately determining that you have filled the tank to the exact same level as the last time you refuelled. Hence, mileage figures can be skewed considerably.

 

Hi cmccarthy. :D If any of us were to read any expert advice on correctly keeping track of true MPG, it will always say to calculate it manually. This is why things need to be done properly. For example, you slow the nozzle flow down as you are approaching full, you do not top off the tank, etc, etc.

 

Also, and most importantly, while you calculate for every tankful, you need to average your calculations over many tankfuls. You calculate for at least 4-5 tankfuls, and then average them together. In the same way that a batting average in baseball is calculated for the entire season, not for one week. Small samples can/will give skewed results.

 

Just like any other calculation, the larger the sample (more tankfuls), the more accurate the statistics.

 

I keep a small notebook in my glove compartment. Every time I fill up (I always fill up, never a partial fill) I note the mileage I drove and the gallons I filled. I use Trip Computer A to keep track of the miles driven, and I reset it when I fill. I never reset the MPG reading in the trip computer (it currently reads 21.5 MPG).

 

I therefore have a running tally of what my mileage was for every tankful of gas since I bought the car. If it seems to drop suddenly, I will know immediately. I also know enough to realize that cold weather, hot weather, winter gas formulations, stop and go driving, A/C use, Defroster use, improper tire pressure, etc, etc, etc...will all drop my MPG's.

 

Now this may seem like a lot of work, but look at it rationally. It takes me 30 seconds to take the notebook out of the glove compartment, fill in the miles driven off of Trip Computer A, reset Trip Computer A, then lastly write down the number of gallons pumped, after I pay. What else are we doing while we are standing/sitting there? Hell, it took me longer to type it than to do it!

 

Everybody should try it, since not only does it help you know how your car is performing, it also makes the time it takes to fill-up pass quicker! :yup:

 

Good luck and Happy New Year! :beerchug:

Edited December 29, 2007 by bbf2530

[sim]

My average is about 20mpg for the 35 or so tanks i have filled up so far, although they do vary from 16 where its all stop-start city (actually we were house hunting a lot at that time) to 23 (tank average, we hit 27 on the computer) when we did long road trips. I have always got better than EPA numbers on every car i have had for the city or highway driving, this car is doing the same for me.

[Mcginnis158]

We bought our Edge in early November. The gas mileage was outstanding when we first got it. (25-30mpg). Now that it is "broken in", gas mileage has dropped to 16-16.5. It is mid-city driving. Not stop and go all the time, but not driven on the highway. When I took it in to our dealer they said they put it on the diagnostics and everything was functioning properly.

My Taurus is now out of warranty and I brought it in to a local service station for its oil change and asked them what they thought. They send with a drop off of 10 mpg that something was going on. They also said a diagnostic check would not let them know why the car was underperforming. They said the diagnostic check would only show problems if the engine light was engaged. Does anyone concur with this explanation.

I just can't understand a drop off of 10mpg. Someone suggested maybe winter gas formulation. I guess we won't know that until the summer comes around.

[bbf2530]

We bought our Edge in early November. The gas mileage was outstanding when we first got it. (25-30mpg). Now that it is "broken in", gas mileage has dropped to 16-16.5. It is mid-city driving. Not stop and go all the time, but not driven on the highway. When I took it in to our dealer they said they put it on the diagnostics and everything was functioning properly.

My Taurus is now out of warranty and I brought it in to a local service station for its oil change and asked them what they thought. They send with a drop off of 10 mpg that something was going on. They also said a diagnostic check would not let them know why the car was underperforming. They said the diagnostic check would only show problems if the engine light was engaged. Does anyone concur with this explanation.

I just can't understand a drop off of 10mpg. Someone suggested maybe winter gas formulation. I guess we won't know that until the summer comes around.

 

Hi Mcginnis158. :D This is an often asked question. I took the liberty of copying and pasting a reply from one of the other threads asking the same question. Hope you find the information helpful and informative. Copy and Paste begins now:

 

Anyway, here are just some of the reasons for your "low" MPG's at this time of year.

 

Please read the following list carefully, as there is at least two factors that you can do something about (#5 & #8):

 

Here are just some of the many (simplified) reasons your car will get lower mpg's in very cold weather:

1 - In many regions of the US, the gas formula is switched over by law to an "Oxygenated" mixture in the winter months, to meet EPA Air Pollution standards. This mixture is inherently less fuel efficient. Your car uses more fuel.

2 - An automobile engine has a specific temperature range where it is most fuel and power efficient. Get too far out of that ideal temperature range, either high or low, and fuel efficiency suffers. So essentially, extremely warm or extremely cold temperatures (summer and winter in most regions) adversely effect fuel consumption and engine efficiency. Once you are out of that ideal range, your car use more fuel.

3 - A car will take longer to warm up in cold weather, therefore running richer for longer. Your car uses more fuel.

4 - Cold air is denser than warm air, so an engine needs more fuel to run properly (just to drive normally). Therefore, the Engine Management System must run a richer mixture, to avoid running lean. Your car uses more fuel

5 - If you run your front windshield defroster, or have the Automatic Temperature Control HVAC system set to "Auto", your cars A/C compressor is running to dehumidify the warm air. It is the same as running your A/C in the summer. Your car uses more fuel.

6 - It takes more energy to get a car moving and keep it moving in wet, icy and snowy conditions, than it does in dry conditions. Think of driving in snow as almost the equivalent of driving in sand. Your tires, and therefore your engine, need to overcome more force against them. Your car uses more fuel.

7 - If you read your Owners Manual, or search this site for information, you will see that the 3.5 Liter engine in the Edge will take at least 5,000 miles to be fully broken in. Until that time, you guessed it, your car uses more fuel.

8 - Since you purchased your Edge, have you checked the tire pressure with a good quality tire pressure gauge? Do you own a good quality pressure gauge? You certainly should. Low tire pressure will adversely affect fuel mileage. Tires will lose about 1.5psi for every 10*F drop in ambient temperature. For example, if you last checked your tires in November, when the temperature was 70*, and now it is 20*, your tires will now be at least 7.5psi low. Plus it is dangerous to drive with under-inflated tires. Check them, and fill them to the recommended pressure listed on the door sticker of your Edge (or preferably 2-3psi higher).

 

These are just a few quick, simple reasons. I am sure someone else will jump in with more. And not that it makes us feel any better, but our friends and neighbors are not immune. Their cars are getting lower mpg's also. If they say they are not getting lower mpg's, they are either oblivious or telling a little white lie. You can't beat the laws of physics and chemistry.

 

Good luck! :beerchug:

Edited January 12, 2008 by bbf2530