Hi all
I was wondering if the cold weather alone up here in Minnesota is enough to drop my mileage down to 13 in the city. I was getting 15-16 in the warmer months. We have oxygenated fuel here year round so I can't blame it on winter fuel. I also don't let the truck idle to warm up for more than a minute or so as I plug it in every night.
Is this common? I never really paid attention to mpg until I bought my 07 FX4 this spring. 12,000 on odometer right now for what it's worth.

 

It is normal. My mileage has dropped as well and we dont have the winter mix.

 

I have noticed that since I've been dealing with temps in the teens & 20's my gas mileage has lowered some, since temps in the 50-80's......so don't feel bad, or alone, I'm assuming it's just normal for colder temps.....

 

Im in northern Ohio, mine goes from 17.8 to 13 in the winter months.

 

In cold weather, it takes longer for the engine to reach normal operating temperature and go into closed loop. In open loop it runs a lot richer.

 

Well, I'm not alone then. Misery loves company, right?

Thanks everyone

 

Has anyone tried fitting a partial-cover on the radiator? I see big-rig trucks trying this to avoid "over cooling" in winter.

Would you have to make your own, or is this available for F-150s on the aftermarket someplace?

 

Cold weather and been in 4x4 for last 3 weeks, no idling as it doesn't warm the truck up and of course no mileage. 04 FX4 Screw 33s, 3.73s. Going to find out next week how bad it can really get when driving down the highway in 4x4. But I'm still doing way better than I did with my 5.2 Dakota 4x4 with 3.73s and 31s

 

I have seen that too but it seems to me it is the temp of the air seen by your IAT rather than what goes on with the air flowing thru the fins of your radiator. Your t-stat is suppose to moderate the water coolant temp by mechanical spring that controls the flow. I run constant temp once the block warms up but my mpg still sux. I have the winter blend so that isnt helping either. I am currently getting about 14 to 14.5 mpg avg in the city where I was getting 17.5 to 18 during the warmer months and no winter blend gas.

I have been meaning to do such but I want to remove the heat shield from my K&N intake and maybe even block the front side where fresh air comes in so I can deliberately pull in engine-bay air and see if that helps. But so damn cold outside.

 

If the temp gets down below -20F then a cold front will help. You can buy a cold front that snaps onto the grill for about $60.
And yes winter blend fuel will destroy gas mileage basically a "winter" blend adds an oxygenate (isoprpyle alcohol) which allows the fuel to burn cleaner when cold. The net affest of which is 10% lower emissions and you use 25% more gas. Up here in Alaska we used to get a winter blend until they found out it gels at -40F, the exhaust from oxygenated fuel made people sick and there was no reduction in our air quality during winter.

 

Alright, here's some info for you guys.
I work where we use fuel density/ vs tempratures. as the temps get colder, density increases. when warmer density decreases. so, at 0degrees celcius, fuel is heavier per gallon.
So, if i buy gas where it is cold, and take that same amount of gas to a warmer place, it wil expand , and seem to be making more gas! when actually, the liquid is just expanding.
Ever wonder why they tell you to buy gas in the morning when its cold? that gas will expand and give you a full tank.
so, to fill the tank in the winter when the gas is cold, the volume it takes to fill the tank is going to be greater than what it is in the summer!! and going to seem like you are getting worse mileage cause you are gettin more gas to fill the tank because the fuel is denser..........

 

Well, being that the tanks at your favorite gas station are several feet underground, you'd have to be somewhere like Vegas or Phoenix or thereabouts in mid-summer to notice that huge a difference.

It's the vapors that are expanding, though...not really the liquid so much.

 

They reformulate the gas for winter. Due to cold temps the gasoline will not vaporize as easily, so they change the formula to include more Benzine (?) that makes it easier for fuel to vaporize. Unfortunately, the reformulation also has less BTU (energy content per unit of measure) than in summer. So the gas you are buying actually has less energy in it, hence, you need more of it to do the same amount of work your engine did when it was using the warm weather gas. Consequently, they use a formula in warm weather to retard vaporization because it gets so hot.

Also, air is colder, and more dense. Your MAF and IAT should pick that up and the PCM reads more air coming in, so it increase the fuel charge going to the injectors to maintain the 14:1 ratio. That knocks down mileage too (theoretically it should increase hp all things being equal).

I have an 03 Ex, 4.6. In summer I can get 19hwy by myself, around 16.5 around town. I am getting about 15-15.5 around town now, maybe 17 hwy.

 

[QUOTE
It's the vapors that are expanding, though...not really the liquid so much.[/QUOTE]

Actually because of the volatile nature of gasoline it expands quite a bit, I learned that the hard way, I filled my 30gal tank at -40F and I squeezed an extra .5 gal in after the automatic shutoff clicked at the pump, I then drove about 2 miles home and parked in the garage, the next morning there was a puddle of gas on the floor.

 

not to resurrect a long-dead thread, but i think this merits mentioning: i have a 2005 supercrew with the 5.4... my typical mileage is about 60% city, but i've never been seeing the kinds of mileage you guys are suggesting. we're talkin 13.3-13.5 TOPS, and now with the temps in the mid-teens to mid-20s for the last few weeks, my mileage is down below 10 all the time. what the %@*$ is going on? I don't drive THAT much so I'm now spending a fortune on gas, but it just sucks looking down and being reminded how crappy my MPG is.... anybody got any suggestions of things I should check? Oil is changed religiously every 3k (not sure that is even relevant), fuel injector cleaner has been run through about every 5-6k miles... air filter is clean... I've tried several things, but it never seems to get any better. Help is appreciated.