Decrease in MPG recently 3g 4runner

[Jetboy]

Anyone in Utah or anywhere else notice a significant decrease in fuel economy over this winter?

I've gone from 18ish around town down to 16 in my 4runner. My wife's IS250 has dropped from 28ish to 25, and my brother in law who lives a few blocks has noticed a very similar drop in mileage in his 97 4runner. I'm wondering if something is up with our gas here. Possibly the 10 or 15% ethanol blend is causing sensor errors and low mileage?

My brother in law first mentioned it. I track every tank and I notice it too.

It's been like this since December or so.

Any idea if something has changed in the gasoline supply?

If it were just me I'd probably figure it was an o2 sensor. I just replaced it last summer though, and we all have had noticeable drops though.


FWIW, I ride my bike to work now most days, so my gas consumption really isn't a lot. Just wondering if anyone else has noticed similar issues, and if there's a good explanation.

 

[ken_79-fj40]

I have a fairly long commute and often track my mileage at fill ups. I notice about a 1mpg drop in fuel economy when they swap over to the "winter blend" gas here in NH in the late fall. My tacoma drops from 20-20.5 MPG down to 19 in the winter. No warming up before driving or anything like that either.

 

[SC T100]

Also, colder air = more oxygen = more fuel needed to burn at the ECUs ratios. You get a little more power in the winter, at the expense of fuel economy.

 

[nspctr1]

Also, colder air = more oxygen = more fuel needed to burn at the ECUs ratios. You get a little more power in the winter, at the expense of fuel economy.

Yep but, you can always check your throttle body and make sure it's clean.... prolly winter blend tho..