Gas Mileage vs Weather Changes

-2016 2WD Tacoma V6


"Winter" months have started to show up in Texas. Oddly, I've noticed that like flipping a switch, my gas mileage has dropped about 4mpg highway over the past 3 weeks. Almost like clockwork with some cold fronts that passed through.

Curious if anyone else notices their gas mileage effected this much by changing weather.

I realize that I'm now in the months of "winter blend" fuel, and winter blend fuel does get worse gas mileage, but I'm noticing a 15-20% decrease in mileage. That seems a bit extreme just for gas blend changes, no?

 

Historically my mpgs drop by several. For me, probably multiple factors adding up.

• Winter blend fuel
• Using remote start (sparingly, but still)
• Longer warm up times burn more
• It's dark earlier, when I use my truck, I'm taking shorter trips (more city driving)

 

Winter blend fuel just dropped my truck from around 22 down to 20.

 

this is my first "texas winter" with a tacoma and I just noticed this. i was 16ish city im 13 14 now.

 

Winter fuel. Bingo!! Always good for a couple in my cars. Tacoma down 2 MPG or so.

 

For sure there is decline in MPG in the winter, especially so if you do a lot of short trips where it takes half of the trip just to get up to temp. My daily trip to the gym is 3.9 miles through town. In the summer I'll average about 19.5 - 20 MPG if I don't get stopped by a train. Winter time, same trip runs at 16 - 17 MPG. On longer trips with more time at running temp it's not as noticeable, but still the winter gas drags it down about 1 MPG.

 

haha... this was actually my first thought. Tire pressure is all good.

Yeah, 90% of my driving is on the interstate. I usually get 22-24 on the highway. I'm now getting 18-20

I'm shocked winter fuel blend can make this big of a difference.

 

I don't know if it's a thing with these engines but my truck HATES winter gas. I also see huge MPG drops that I've never seen with any other vehicle.

 

Interesting. I noticed a small drop on my last fillup. I did my small lift and tires back in April so this will be the first cold weather with my current setup. I am running around 17.5 now.

 

For those getting poor cold weather mileage, check your tire pressure. You’ll need to add air compared to summer month driving.

 

Winter blend gas and decreased efficiency in colder temps, im currently getting about 16mpg in the city. That, and i remote start about 5 mins before I leave on 1st start up. All pretty routine.

 

My experience is that the drop in mileage is almost completely due to cold weather and the time it takes for the engine to warm up. In the fall and spring where I live, its not uncommon to have temps below freezing one day, and the next day, temps in the 60s. On the same tank of gas, and same routes, I'll see mileage go from 19 on average to 15 on average with a 30 to 40 degree ambient temp change. It appears the engine runs very inefficiently when it is cold, and it takes a long time for the engine to get up to normal operation temp with below freezing temps. I can drive 5 miles in city stop and go traffic, and still not get my engine up to temp by the time I arrive at my destination.

If you look at the eco guage, when it is cold, you will see that the mpg is quite low for the first 4 to 5 minutes of driving, then all of a sudden, the mpg will start to increase back to what one would normally see under normal operation. If I had to guess, the Atkinson cycle probably doesn't come online until the engine reaches a certain temp. Everything I have seen with my truck indicates the engine runs very inefficiently when in Otto cycle.

 

Excellent answer, gasoline has the same energy content throughout the year. They just increase the RVP during the cold months

 

Make sure to change out your diff fluid to winter blend as well, helps keeps everything lubed right.

 

Also don’t forget to change your blinker fluid to winter blend

 

Check tires, as already mentioned.

Also, pay attention to the time change. People are groggy and its going to subtly change the traffic patterns around town. If you start watching for it you'll notice that a lot more people than usual are mindlessly tapping the brakes when rolling in traffic. Those little bitty speed corrections kill mileage way more than weather or fuel blends.

My mileage started piss poor after the first cold front, but its back up to almost normal now.

 

what psi is everyone running?

k02s specifically?

 

I was getting 20-21 mpgs during the warmer months and now I'm seeing 16-18 mpgs. Kansas got hit hard with winter weather pretty quickly. So I noticed the change in MPG's immediately. I don't know much about winter fuel blend, but if that's the case, then it makes sense. Also, I'm guessing that the colder air temps affect the fuel efficiency in various ways.

 

Yes winter gashole does that. Or perhaps the 6 inch lift and E rated 38”s you put on before you participated in Street Outlaws last night had something to do with it?

 

What size?