I have a 2006 Prius bought last summer. Initially, we were geting
46-49 mpg on it, but the mileage has been steadily decreasing. By December, it was down in the low 30's, and in the last few weeks it's been in the 20's -- 23 on the last tank.I expected the mpg to decrease in the winter, and it's currently cold in Chicago (from -10F to maybe 18 over the past couple of weeks), but this is much below my expectations. I've done web searches and haven't seen any other mention of this problem to this degree. (pun intended) The car also seems to be "dieseling" at stoplights.
I took it in to the dealer, who did a 27 point checkup and an 8 mile road test, and basically said "it's cold -- that's the way these hybrids are in the cold." He said the "dieseling" was just the gas engine turning on and off to keep the car warm.
Is that anyone else's experience, or should I keep looking for a cause/ cure?
Thanks.