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winter MPG

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Old 01-11-2010, 02:57 PM
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Default winter MPG

hey all, just wondering if its just me and my car or if winter gas mileage in my 06 gxp straight sucks? can using remote start ALOT suck gas and just plain winter driving conditions suck gas also, i normally get about 280 miles on a full tank, lately ive been getting 180ish,,,, im on a quater tank right now and have 125 miles on this tank. i use premium everytime. Is this normal?

thanks, Levi
Old 01-11-2010, 03:12 PM
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I run premium as well and i get about 27 mpg with dod, 25 without it. I get around 250 per tank regardless. Im running a pretty aggressive tune all year round which i was alittle hesitant to run in winter but all seems fine so far.
Old 01-11-2010, 03:14 PM
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i was seeing about 18 mpg on average during the summer and now i am seeing around 15 mpg on avg....same thing happened last year.
Old 01-11-2010, 03:21 PM
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I get like 2mpg in city and about 17 on the highway now, My tune is all messed up but its been like 20degrees every day here so i am sure that has something to do with it.
Old 01-11-2010, 03:36 PM
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yeah i was thinking gas mileage when i bought this car so it doesnt really matter to me just was making sure i was loosing mileage from something
Old 01-11-2010, 03:44 PM
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i just talked to two other people at work and their gas mileage went down by about 2-3mpg now as well
Old 01-11-2010, 04:24 PM
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i do about 98 % city driving as well so that doesnt help me much
Old 01-11-2010, 04:27 PM
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im hoping to get dod tuned out, as i have read that city mpg will increase a tiny bit
Old 01-11-2010, 04:33 PM
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Doens't "winter gas" have a different blend that lowers mpg?
Old 01-11-2010, 04:44 PM
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Yup - we're noticing it up here in Michigan - I'm losing a .10 in my lifetime mpg a month
Old 01-11-2010, 04:46 PM
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Remote start is only part of the story. Until your engine warms up, DOD and DFCO (Decel Fuel Cut Off) aren't enabled and it takes longer to warm up in the winter (obviously). Also, your torque converter won't lock until the transmission warms up, and in the winter it's usually the engine coolant that warms the transmission fluid up so there is a decent lag there too (you can watch your trans temp increase faster after the thermostat opens). Combine all three not kicking on until you've driven for a bit, throw in higher viscousity fluids, and you lose a lot of mileage unless you are travelling long distances. Also, I slip the tires a lot more in the winter and so I can't accelerate as hard. You want a decent load on the engine when accelerating to get good efficiency, so you lose mileage there too. Firm acceleration (not WOT, lol) without overshooting your target speed followed by a steady light foot gives the best mileage for most cars. Finally, pusing through slush and snow requires more torque than rolling along dry pavement, hurting mileage more when the roads aren't plowed.

The other part of the equation is winter gas. Winter gas is reformulated with additives (a google search of winter gas in your state should kick them up if you are interested) that help the gas vaporize and increase octane rating. But, with higher octane and lower density fuel you have less energy per gallon and so you get worse mileage.

FWIW, I got 19+ in the winter and 22+ in the summer before I started modding, but I also run winter tires which have a higher rolling resistance too. I was at 22+ after my MAF tune until the snow hit, now it's slowly creeping down.

Final Tip: make sure you put some more air in your tires because colder air is more dense and your tire pressure drops when it is cold (pV = nRT).
Old 01-11-2010, 04:47 PM
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where you at in michigan? i only use shell gas
Old 01-11-2010, 05:40 PM
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using shell gas might be part of the problem. Shell will produce more knock than other providers.
Old 01-11-2010, 05:47 PM
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Winter gas, longer to get into closed loop, longer remote running times, etc.
Old 01-11-2010, 06:39 PM
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I got 16.7mpg on my last tank, with temps averaging 40 degrees. So I'm not down too much from normal.
Old 01-11-2010, 11:27 PM
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what gas stations do you guys use?
Old 01-12-2010, 06:34 AM
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Mobil, BP and Sunoco are good gas stations. I'd recommend either of these...
Old 01-12-2010, 10:14 AM
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i dont even think there is any of those in my town, mostly shell, citgo, speedway, meijer , and marathon. those are all of the gas stations in my town, i google mapped it and thought about it, there is a sunoco about 15 miles from my town tho, would it be worth it to go there?

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Old 01-12-2010, 10:37 AM
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Originally Posted by 94ss06gxp
i dont even think there is any of those in my town, mostly shell, citgo, speedway, meijer , and marathon. those are all of the gas stations in my town, i google mapped it and thought about it, there is a sunoco about 15 miles from my town tho, would it be worth it to go there?
im in the same boat as you...clostest i got is a marathon so hopefully someone can chime in on that one.
Old 01-12-2010, 01:08 PM
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What MPG??? I stopped watching that when I bought mine



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