Has less than 8000 miles. After 4000 miles and getting 48.6 mpg was going up slowly rising 1/2 mile hill when car suddenly surged almost all the way up the hill on its own (wasn't using cruise control) then just quit. Prior I was averaging 48.6 mpg calculated. The last 8 fillups have ranged from 31 mpg to 37 mpg calculated going the same trips as before. Taken to two dealers and they say theres nothing wrong with the car, that there's a air bladder in the gas tank thus barometric pressure is whats causing the different mpg and I shouldn't pay attention to mpgs as most prius are getting the same mpg. Also having trouble with ev system shutting off at 8mph coasting on a flat road with battery fully charged, dash message states going to fast. Dealer couldn't find nothing wrong with this either. Brakes squeek at times, dealer stated nothing wrong with that either. I have contacted Toyota "we care" 3 times, and am told somebody would get back to me in 24 hours. Doesn't happen. THEY DON"T CARE! I'm wondering if Toyota is giving dealers bonuses not to fix cars. By the the way, about 3 miles after I left the dealer I stopped at a store and a woman getting into a older Ford when I pulled up said, " Your car sounds sick, its making weird noises."