I was qiestioning the same thing when I got my s40. Usually I fill up the tank and reset the trip computer. The mpg is not accurate either, but i estimated the eror. As a general rule it is about your trip comp mpg times 15 galons make my mile range, although it worked, I usually stay on a safe side...

check if that main gaint nut ( not sure how you call it) that holds wheel assembly to axel is tight. Or bearings.

The body style does'n look like 2009, it is 1999-2004, I think it is 1999 and he made a mistake

I have had s40 2001 for 6 years. I got it it with 51k and it's 183k now. Good fuel economy at speed 80mph it is about 30mpg, it is beter at slower speed. At about 60k had misfire, had a hard time to find the problem, original volvo spark plugs fixed the problem. Somwhere about 110k had to replace fr...

I had a same problem on my s40 few years ago, first I replaced spark plugs to bosch, then NGK, then I replaced the coils, these didn't fix the problem. When I installed original volvo spark plugs it did fix the problem. I don't know if it has something to do with turbo or who knows. so try that befo...