Unfortunately, these cold Canadian winters drink my gas like nothing and I struggle to get 310 miles out of a tank, ending up with about 260 miles on the trip computer when empty. Recently been getting 18mpg combined while in the summer, I averaged a solid 22mpg (my car is from the US)

Very curious to see how others compare right now. Not sure if mods will play a part in this, but I have a KN intake and straight pipe muffler delete.

Summer I get about 22 MPG/ Winter I'm getting about 19-20 MPG. Texas weather is not really cold. Only mods I have is a drop in AEM filter, and Apexi throttle controller. Also the charcoal filter is removed from the top air box lid. So I'm letting in definitely more air in.

Had been getting about 24-25 MPG this month, last summer got 25-27. That's on my '06 IS 350, with a 50 minute commute to work. This week I'm off from work, doing lots of short trips around town, and seeing mileage plummet to around 20.

Terrible!
Which is why I take the bus and leave the 88 325is and 06 IS350 at home in the garage!

Pretty bad... I usually average like 10-11L/100km (24 MPG?) now I get like 13L/100km (20 MPG?), car barely gets time to warm up in 30 min commuting traffic for me

I get 22-23 mpg all year round.

I have an '09 IS250 and I just filled up. Travelled 608km on 51L of gas. I'm pretty happy but i usually get closer to 700km on a fill

This car continues to amaze. Just hit 24.5 MPG average. The darn G37 never gets better than 18.

Are you guys calculating the miles or going by the trip computer? My computer is telling me I'm around 26 mpg this winter.

i used a fuel app

i use my own calculator after every fill up

Summer manual calculations.... 60% town/40% fwy

IS-350 MPG (17.0 gal max)
297.0 / 14.40 = 20.63 mpg
327.6 / 12.66 = 25.87
284.0 / 12.83 = 22.13
293.6 / 13.60 = 21.58
293.5 / 13.76 = 21.32
250.1 / 11.84 = 21.18
325.6 / 14.76 = 22.05
289.2 / 13.96 = 20.71
299.2 / 13.66 = 21.90
299.4 / 14.53 = 20.61

Winter... Im getting about 1.75mpg less fueling at 260/275 mi. Temps are in the 30°F....
It takes about 3.5 mi of traffic to the freeway to get the temp gauge to its normal 6 O'clock position.

I'm honestly jealous after hearing all of this. Just put in $30 of 91 for the time being, got half a tank and 140 miles of range. Used to get 160-170

Also, I noticed there are some GTA locals in here. Where do you get your gas from? Personally, Husky did me so well this summer. Got more range and burned better compared to Costco and Esso and what have you.

i use costco gas. i don't see a difference in MPG between shell, exxon, valero, costco, ect :shrugs: