the MPG is dropping on my 2008 Prius, dropped about 10%, so 5mpg less. I recently put a new set of Tires On, bought from Costco, Michelin. The car is about 100k miles. I noticed sometimes, when not press gas paddle, the MPG don't jump to 99Mpg as it used to and sometime on Freeway when maintain the same speed, before the MPG would be easily over 50 even at 70-80 easily, now it goes to 40. is that indicate the battery is old? BTW, for the 12v battery, I had Toyota replaced it for me in 2010 spring when the car is at 25k, (since back then, one day the car won't start) if I replace it now, will it improve MPG? Thanks.
What model are the tires? Michelin makes tires that range from great to terrible for mileage. What tire pressure is in them? The 12v battery is probable fine unless you've run it down before. You can test it and see, but I think the tires are probably your problem.
Please copy and paste the survey into a post here and answer all of the questions in the survey. Then we will have a good idea of what is going on and be able to help you. Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat Also, there is a broken link in the survey. Please ignore that. Many links were broken when the forum was redone a while back.
