after my last maintenance visit to the dealership, and ofcourse tire rotations are done - my gas burns 3x as fast! im averaging 25 to 35 mpg at most. i can drive 2 miles and check my odometer and it already burned equivalent to 6 miles as if i drove further. i mean i tested it again and a trip that is about 12 miles, burnt through as as if i drove 27 miles. HELP??!!
I hope tour odometer reading is t giving you wrong values, as comoakined by other people with problematic odometer on that model year of Prius? Forget the odometer reading. Y not calculate it manually, and see if your MPG values tallies with the one on display? PS: You could use your TRIP A settings on the dash to confirm it.
You won't REALLY know if that is true or not until you drive a substantial number of miles.......maybe 100......and fill the tank again to see how much it takes. You can NOT trust the computer displays to be that accurate. But it is good that you noticed a potential difference.......because there could be a problem there.
If the 12-volt battery was disconnected for some reason by the dealer it may have changed the calculated fuel mileage. After a bit the readings will change back to what you have been used to.
Battery disconnection does reset all trip meters. If you're calculating your mileage and don't want any gaps, the most bullet-proof method is to record the odometer at each fill-up. This is good too, say if someone borrows the car and throws in $10's worth: as long as you can find out just how much they added, you can lump it in with the next fill up.
Might be when they rotated the tires, they undid the calipers to check brake pads, and then put it back on incorrectly causing rear drag.