Lower MPG in warm weather.

When idling, and low speeds that snorkel may be of some value.

 

Yes. Yes it does.

 

Seeing how your temp gauge is showing 119 F, I'd have to assume the reason you're using more fuel than normal is due to your A/C system being on full blast quite a bit. Summer blend gas is usually more fuel efficient than winter blend gas, so you can expect gas mileage to actually be a bit worse in winter than summer... but A/C systems put enough stress on your fuel system for you to notice a drop in MPGs if they're consistently being used.

 

Winter blend gas is usually worse for MPG. Better for starting and running in the cold, but worse for MPG.

 

Many have mentioned the AC system. Idk if your thermometer is accurate or if the truck has been sitting and not driven (since it tends to read hotter after just sitting there), but putting your AC on recirculation should help a little. We'll get into the 90's where I'm at, but never 119° so I imagine that the AC has a lot to do with it.

 

Yeah, plus it takes a lot longer for the engine to get up to temp during the winter when it colder. Short trips are really a killer.

 

It must be great knowing the engine generates more power while idling. Rather than making 10hp, it is making 11 HPs all thanks to the snorkel!

 

I drove about 12 miles this morning, in the cool mid 90's, and the average mpg went up to 18. I probably have 24 miles on this tank of gas. drove the same way both times so I'm just showing the difference.

 

Thanks for the update. Shorter trips will kill it too. 24 miles isn't much to go off of, but I'm assuming this isn't the first time you've seen this so I'm going to take that out of the equation.

 

It's due to changes in Density altitude , as it gets hotter ( ambient air temp) the corrected elevation changes . This makes the air feel like you're at a much higher elevation ( thinner air less O2)


Just to give you an idea what im talking about and using a Density altitude calculator and inputting info such actual elev , temp , pressure and humidity

I live in the High Desert elevation of 3200ft and my DA or corrected elevation right now is 8800ft corrected

 

It’s not just running the A/C that kills summer economy, the A/C actually has to work harder due to the temperature differential being so great.

 

Use this Air Density calculator to find your corrected elevation

https://wahiduddin.net/calc/calc_da.htm

 

That puts me at 4,291. We are 272' above sea level and it is 117 right now out there. That is a really cool calculator, thanks.

 

I'm a Drag Racer and and Density altitude calculators are a very important tool to use

 

Summer gas blend + driving around with the AC on.

 

High density altitude also means less fuel to match the less o2, unfortunately it also results in less power from your normally aspirated engine.

 

Summer gas is more efficient than winter gas so that's not going be what hurts his MPG.

 

Same here. Back down to 17 during the winter.

 

I have researched this thoroughly and altitude and temp are key to mpg.

 

Also are you using ethanol enriched gas...very poor at getting the full efficiency