And, if the dealer has had the car for a month, ask for the Toyota Prius specialists from the Zone/Region to be called in. Generally, a manufacturer will have experts located in each region of the country who specialize in hard to diagnose problems with specific cars or even engines. They are super trained and know how to use the diagnostic equipment at a level the dealer's mechanics seldom reach. They can coach the local mechanic and even visit the dealer occasionally for the really tough ones.
Yea, I'd check your tire pressure and reduce your speed to no more than 70 MPH. I don't know why, but the dealer always sets my tire pressure to 35 PSI, I promptly pump it back up to 42/40 front/rear. I get much better milage with the proper tire pressure. Sadly you CAN'T trust the dealer to set the tire pressure the way you want it. Get a digital tire pressure gauge and use that once per month.
She's owned the car for 18 months, 80,000 miles. Presumably, this would have included more than one winter. Not to mention, her driving style proably hasn't changed from when she got 30% better mileage. I'm now getting 40+ with my snow tires on, so that's not it. No question, tire pressure higher is better. I would presume that something like a brake caliper is stuck. The LRR tires and whatever would not add up to a V getting 30 mpg. Right now, I get better mileage rolling at 75+ on the interstates, better momentum through the hills.
Thanks for all of your suggestions. The dealer was baffled also, and agreed to a very fair trade down to a standard Prius. I find it funny that they are now advertising my old V on their web site with the 40/44 mpg rating, but it's not my problem anymore! Thanks again
My PRIUS II (2011) just went through the software recall. My mileage in town has dropped to 38 mpg. Did you get the recall done?
I have the same problem. My 2010 prius is down to 36MPG, never really experienced the 50MPG. I live in socal, I noticed during summer the MPG drops significantly. I just has service done last week and the best I got was 36.
Toyota did not make a v wagon in 2010 so I assume you do not own one. I suggest you start a thread in the Gen 3 fuel economy forum.