Little loss in fuel efficiency

[METHLAB]

I typically get somewhere between 375 and 400mi per tank of gas. Lately I have been getting 340-350 per tank, that's significant when driving to Boulder every day now. It's 23mi one way to work. three nights a week I take 287 (120th) up to Pecos for school and down I25 home at night. This burns ALMOST 1/4 tank of gas. I remember the days of 90mi/quarter tank. I'm driving 65, 6th gear and staying out of the turbo unless needed. Could my SRI just be dirty? Now that I'm driving so much it is noticible, I perused the forums a bit for a resolution but didn't really find it. Thanks guys.

Shane

[AIM WO4]

I dunno. I threw a DashHawk in, and now get 400+ miles as opposed to 270-300 just by watching my acceleration.

[Anh Bi]

How long do you let your car warm up during the winter? I've noticed long idle to warm up the car in cold weather does affect my mileage quite a bit.

The other culprit would be ethanol. But I am not sure if they increase its dosage during the cold months.

[METHLAB]

Not a very long warm up. 5mins usually, I take it slow tho, I don't jam it. I'm gonna re-check my tires, air filter etc this weekend and see if I notice anything. Thanks ya'll.

[milehighspeed3]

Are you on winter tires? I drop about 3mpg on the winters...

[206b3]

I'm nowhere near 27mpg going from Lafayette to Jeffco (RMM...sorry) or to Boulder. 33mpg open highway but only 340 per tank when the warning illuminates. I don't drive hard at all but I must be driving a lot harder than normal. My Speed is stock with I-Pike 205-60 16's snows. 5000 total miles

If one can get 400 per tank in winter then what do you get in the summer?

Shouldn't your mpg's decrease in the winter? The air is cold, more dense than summer so more fuel is consumed per base fuel/air ratio.

My average mpg is 24.4 based on records, the trip computer says 26.9.
I'm in sixth frequently for economy

Maybe my speed is f-upped. How do you stay out of the turbo?

[RX-7 Chris]

I get about 300 to a tank and I have a 16 gal. so I don't think you are doing too bad.

[bobopud]

Winter blend for gasoline will decrease your mpg by quite a bit, couple that with a dirty air filter, insufficient air in your tires, and the colder air temps and you could see a significant drop in mpg.

[METHLAB]

Winter blend? Sorry bobopud, what is that? I did put 2 new tires on my car a couple weeks ago, but they're all seasons and they are they same size, 215/45/18. Funny thing, I filled up again today and had to do a bunch of driving, im at almost 90mi on the first 1/4 of a tank. Odd, also, when I filled up I had 300 miles on my tank, I put in 12 gallons. Call me crazy but that's 25/gal!! Not what it seems, my fuel consumption gague says 26.6... grrr! lol

[SpeedDemon]

Are you on winter tires? I drop about 3mpg on the winters...

Same here I normaly drop about 3-2mpg with my winter tires on.

[Gmoney]

I am seeing the same, went from about 400 a tank to 340 a tank. I have 4 heavy blizzaks on though. I know the extra ethanol kills mileage as well, just cleaned my intake and got nothing more this last tank......most likely the gas IMO......Spring is getting closer:D

[bobopud]

The chemical composition for the majority of gas sold in this country changes with the weather. I don't know the exact science behind it, but more ethanol is added to gas in the winter months. The more ethanol you add the lower your mpg's go. In the summer months there is less ethanol added to the gas and your mpg's get a bit of a boost.

http://ask.cars.com/2009/02/whats-the-difference-between-summerblend-gasoline-and-winterblend-gasoline-does-it-affect-my-cars-pe.html

Here is a website that does a basic overview.

[METHLAB]

Awesome! Thanks for the info, much appreciated!