Volvo: poor gas mileage-2000 Volvo V-70 XC Turbo Wagon (75K miles), poor gas mileage, high fuel mileage cars

Question
Question by Kent.  Victoria's Volvo gets pretty poor gas mileage compared to Kent's 2002 Subaru Outback (2.5L). She gets, at best, 19mpg on highway (Kent gets about 26-28 and about 13-14 in-city (Kent gets 19-20).  
On the way back from friends about 60 miles So. from Seattle yesterday, the Volvo's Engine Check Light went on.  Victoria had just received, a few days earlier, a recall notice on the ETS system.  Would this account for her poor mileage? We have changed the air filter, but not fuel filter nor sparkplugs.  The car had 68K when Victoria purchased.  Her previous car was a '93 Honda that got 30mpg on the highway.  She's bummed and thinking about selling the car.  

Answer
Kent,
Yes the recall that was for the Volvo could be the gas mileage and check engine light problem. However I will say that I doubt that the Volvo will ever get the same mileage as the Subaru, there are big differences between the two. Volvo has never been known for high fuel mileage cars. Look on line to see if you can find an EPA mileage chart for cars, that way by using the mileage you would like to receive, you can see what vehicles are in that range.