2010=50MPG 2012=38MPG?

Other drivers, other conditions, and repeated short trips (especially on a used car lot) could give it a low trip mpg. I'd ignore that, and use your personal results as a better guide.

Can you check the tire make & model (are they non-original, not low rolling resistance) and if they are underinflated?

 

Sorry but test drives are a poor diagnostic unless you have enough time, an hour, to handle warm-up and a well planned benchmark route. For example, I bought a used, 2003 Prius in Fort Worth and drove it nearly three hours, 'Texas I-20 style', to Shreveport LA . . . 39 MPG, not the 52/45 City/Hwy MPG!

I briefly thought about turning around and taking it back. But I asked myself, 'How can a government bureaucrat get better than 39 MPG?'

So the next segment, I used cruise control at 60 mph and got 53 MPG. It was 800 miles back to Huntsville and I found there was a 'knee in the curve' at 65 mph, 52 MPG versus 70 mph, 49 MPG and 75 mph, 39 MPG.

Still, you need to be happy and buying a car is a significant expense. I was tempted to return the car but instead used the initial, low MPG as a challenge and eventually mastered the car.

GOOD LUCK!
Bob Wilson

 

My guess would be you don't have a problem here. I mean I wouldn't trust a MPG reading that I hadn't read or set myself.

But my concern is that you are already concerned. And I suppose it is possible the vehicle could have issues that are affecting it's MPG.

The dealership should WANT to sell you the new/used vehicle. I'd ask them if you could take it for a significant test drive. Seriously, like an hour or two on the highway, or maybe even if you could "rent" it for a day or two. If they will let you rent it..rent it for a week and see how the gas mileage responds.

It's a used vehicle with 31,000 miles on it...you putting an additional 50 or more on it, shouldn't matter.

Then you could see before signing on the dotted line if the MPG is a problem or not.

If you aren't comfortable with it before you've bought it, then you are getting off to a bad start with a new to you vehicle.

And since you have owned a Prius before, I think concerns about MPG valid.

Once you sign on the dotted line...the vehicles yours. Even though my guess is that the chances are rare, Yes, I'd rather establish whether there is a problem before I bought the vehicle.

 

Try 85 mph, 104f degrees, driving into 35 mph side wind!!!
Yep! 38 mpg. 550 miles, two tank fills.

 

my guess would be that on top of the 600 miles they turned the car on at the dealer's lot a LOT (if nothing else to check it charge the battery ) and/or moved the car a few dozen times going a mile or less a time ... that kills the MPG in a hurry...