Ive noticed that its been a little colder than usual, but on my last tank I got 306 kilometers = 186 miles, for the 60 liter tank=16 gallons. Now its been on average -25 at night and -15 during the day, past 2 days its been dipping below -35 and -40 Celsius!!!!!! Cold i know, but I dont speed, or anything just casual drive to and from work etc.

Can it just be the cold, or could there something wrong?

 

thats pretty damn horrible, must be a problem with your fuel system.

 

There are few things that can effect fuel that greatly, but here are a few:
Short trips. - Short enough that the engine never fully warms up.
Clogged Air Filter - makes it run rich
Under Inflated Tires - excessive rolling resistance
Lazy O2 Sensor - can't accurately respond to changes in exhaust conditions
Sub par Coolant temp - ECM never reaches closed loop operation

just some idle thoughts

P