To buy or not to buy a 2nd gen Prius... Fuel economy?

welcome!

that should get you 50 mpg, in a well tuned vehicle

 

My 2006 Prius gets 46 to 48 mpg (real world gas mileage - mix of local and interstate) in winter here in the northeast US. My mileage has improved since purchase. I attribute mpg increases in my Prius to the following: i.) new air filter, ii.) new spark plugs, iii.) oil catch can and new PCV valve, and iv.) my own better knowledge on how to drive the Prius.

Make sure to "test" the HV battery before purchase. The HV battery test (this test is often referred to on this site but I do not know the test's origins) goes something like this:
i.) reset MFD mpg calculations at beginning of this test (IOW MFD should now show 0 miles and 0.0 mpg at beginning of test).
ii.) drive Prius on as flat a road as possible at 60mph using cruise control with no other electrical accessories (turn off fan, radio, lights) for three to four miles, and
iii.) at the end of the test of three to four miles note the calculated mpg.

If I have not stated the test correctly or accurately then please jump in and provide correction.

The noted mpg is an indication of HV battery health. My understanding is as follows regarding mpg noted for Gen2:

>51mpg: Prius is operating as if it is well maintained and has a brand new battery

50mpg: Prius is well maintained with a very good used battery

48mpg: Prius runs well with an adequate used battery

<40mpg Prius likely has a failed battery

Make sure that no Check Engine Light (AKA CEL) is on before the test. As a CEL will often cause diminished gas mileage and therefore affect the above results (despite the CEL often not being battery related it will often affect mpg - think misfire or bad catalyst for examples).

 

The only 3 things I will add is, before conducting the test:

• Check tire pressures are 33 PSI Rear and 35 PSI Front.
  
• The test should be conducted after the car has been driven for 15 - 20 minutes and is fully warmed-up and in stage 4. See the link in my signature Hybrid Warm up: 5 modes of Prius Operation..
• If you have cruise control, use it.

I would put this as number 1 and my number 2 would be check tire pressures are 33 PSI Rear and 35 PSI Front.

The time of year makes a big difference. If the outside air temperature is 11ºC or less you will not get as good economy as it is above. The best economy is gained at 22 - 25ºC

11ºC = ~52ºF
22ºC = ~72ºF
25ºC = 77ºF

 

A 12 to 15-year-old Prius is close to needing a High Voltage battery replacement. If you can find one that has had the HV battery replaced
that is worth looking at. If not, any fuel savings probably disappear when the battery needs to be changed.

 

An older Prius is definitely going to cost more to operate than the Aygo/Corsa or others listed. It's also a nicer car, I can see why you want it.

 

Yes. It's rather time-consuming, and you have to start doing it before it's too late, and even when you do it all properly the battery will need to be replaced.

Get one with a known bad battery, get it for a low price, put a brand new Toyota battery in there and enjoy a decade of top performance. Costs less & drives better in the end.

 

The main thing is to learn how to drive a Prius in the correct way in order to gain the maximum fuel efficiency.
Lots of articles on the internet about it for you to look up.
Don't drive it how you would a normal petrol car.
Also, as was said earlier, keep the tyre pressures correct as that certainly helps.

 

Average miles per gallon in gen 2 Prii are 42-44 mpg, according to Fuelly. Mine gets roughly 45 mpg.

 

A gallon here (UK) is equal to about 1.2 gallons in US
My average over the week is about 58-60

 

That's about right what I get on the city.
Last year my average was 45.7 MPG w/ a lot of freeway driving 65 miles a day using 195 / 65 / 15 tire.
Now its 44 on city stop and go driving using the standard 185 / 65 /15 tires.
But I don't pump my tires more than 37 psi just for personal reasons. But I heard there's a lot of people put more air and they get better mileage. Either or anything above 32 mpg is already an excellent contribution to your wallet and the world crisis.

 

You will get exponentially less benefit going higher than 37 PSI.

Your "better" MPG on the 195/65/15 was more than likely not real, but largely due to the slightly larger diameter. The correct proportion for the 195 mm tire is 195/60/15.

 

depending on age of the car and time of year it varies. i get between 40-50mpg ( in the usa ) my daily average speed is maybe 35-45mph