I have a 2006 Prius with 165K miles. My MPG suddenly went down 20% (47 to 38). Tires are fully inflated. I did change to high-mileage oil at last service, could this be the cause? Thanks in advance for any input.
I am having the same issue with my 2006 Prius - mileage gone from 50 to 38 and all service done at dealer every 5K. I would appreciate any information or guidance to regain my mileage.
These threads are started with the usual questionaire: Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat
Not likely that the difference in oil is a factor at all........unless you put in something like 20W50 and it's still cold where you live. If your 12 V battery is over 5 years old, I'd recommend changing it now. After that, you need to get a scan done because a really LOT of things could be factors.......like a dragging brake just for instance. Some will show up on a scan and some won't. You need a good mechanic.......but those seem to be rapidly becoming extinct.
