I wouildn't trust the digital readout, what is she really getting for milage. Miles driven divided by gallons pumped in? That is the most accurate way of getting mpg. My wifes car is off 15%, that alot in my book. Is she letting it warm up for half an hour everyday? My truck has been known to get 2-3 miles per gallon in the winter, then again I rarely drive it-2002 K2500 with 8.1 gas hog, pocket drainer and optional 4.10 rearend. I get 8 mpg on a good day.