Better MPG in warm weather?

Some say it's true others can't tell the difference.

But has anyone with the new Taco notice an increase in MPG while driving in warmer weather?

I can say this is true in my case. I drove from southern California to Denver and noticed a hit on MPG average. From 75 degrees to 40 degrees I saw a drop of 2 MPG(24 Hwy MPG vs 22 Hwy MPG). Other factors like altitude may also play a fact.

 

Altitude definitely plays a factor, probably the primary reason you noticed the change. Engines are less efficient at higher altitudes, and the difference between socal and denver is considerable.

 

Air is more dense when it's cold. The air to fuel ratio changes. Your computer then remaps the fuel injection and it will increase the amount of fuel injected. Thus impacting the MPG

 

^^ This.

 

Plus it's uphill

 

To be honest you may notice a difference more then others because of your Atkinson cycle type motor. Your intake valve is being held open longer then others, thus your forcing more of that cold dense air into the cylinders through lower then atmospheric pressure, and given the altitude your running at, that would make allot of sense to see a change in MPG.

 

I have a 2nd gen 2015. Air temp seems to play a large role in my fuel mileage. I saw a sudden 2-3MPG drop once winter and the winter blend gas hit the market fall of 2015. I also tend to get better fuel economy on my drive home than my drive to work (according to a live MPG estimate on my Ultra Gauge). Granted that 20 mile commute covers a 400ft elevation difference.

 

Winter blend gas affects mileage too but I don't know the details or when the change occurs. Fill up before last my mileage increased 1 mpg, however I wasn't driving the same routes so that's inconclusive.

 

It was pretty obvious here. My gas station suddenly had a "Contains Ethanol" sticker on their pump that was NEVER there before. That tank of gas, and every one after it, I saw a consistent 2-3MPG loss. That same week is when 'winter' hit. We've not had consistent temps of more than 45F since.

 

I am not sure that it matters, both Atkinson "simulator" and Otto cycle are sucking the same air and fuel with similar environmental variables mostly based on driver input. Atkinson keeps intake valve open longer in order to push air and fuel back out of the cylinder during the compression stroke, thus only using enough energy during the power stroke to overcome frictional/mass losses and a little more to keep the truck moving. The OP's fuel efficiency hit is likely due to colder temps (denser air=more oxygen=more fuel injected to achieve proper stoichiometric ratio for efficient combustion), and possibly winter blend fuel (i.e. higher butane levels=less energy per volume of fuel) still being used in the area due to colder climate.

 

I disagree. The intake valve staying open longer is going to suck in more air, more colder denser air. So if it's sucking in more dense air the truck is going to compensate more and throw off his mpg even more then a engine without. So I believe it does directly apply.

 

Otto cycle engines pull in air until the piston hits bottom, then the intake valves shut and the piston moves upward into the compression stroke. Atkinson simulator pulls in air until the piston hits bottom, and the intake valves stay open while the piston is moving upward into the compression stroke, which forces air/fuel back out through the intake valve opening. Sometime during the compression stroke the intake valves close. This means less air/fuel is used, with the endgame being better fuel efficiency with less power produced. In case you're wondering where the air/fuel that is forced back out of the intake valves goes, it's been explained that it is timed so that another cylinder sharing the same intake manifold is pulling in air/fuel while the original is pushing it out.

Not trying to be argumentative, maybe I just don't understand what you're saying.

 

I fully understand the Atkinson cycle. Also don't mean to be argumentative, i don't think we are going to find a happy medium here, so all i was trying to get by was, that a you can't be surprised when a engine specifically designed for more efficient use of air gets worse gas milage when that air density / temp is changed.

 

Agreed

 

Yep ethanol blends reduce the efficiency thus lower mileage for the sake of emissions