2019 Toyota Prius - MPG

MPG not as advertised. General is about 46. Long range trip about 47

I would advise a change of shoes. Your right one may be a bit too heavy.

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Not sure of your purpose. Are you just broadcasting this fact or are you asking a question? Either way, it’s difficult to determine whether a fuel economy result is meaningful in the absence of more detailed information. For comparison:

We have a 2019 Prius (Gen. 4) with ~4500mi, purchased new ~ Memorial Day. From day 1 it’s averaged ~ 61mpg (based on fill ups, the dash display says 62.3mpg) over a mix of many short (2-4mi.) hops from an initial cold start and 8-20 mi. trips at freeway speeds. Typical 20 mi. days run from 55-70mpg by the dash display (the lowest was when driven cold up hills). It takes about 5-6 mi. from the initial cold start for the overall trip average to reach the mid-50’s and by 12mi. it’s into the 60’s. On a 450mi. fully loaded round trip to 6500ft. elevation it got 59.5mpg while keeping up with traffic. We try to drive smoothly, following the economy display’s guidance and decelerate early for red lights, but don’t hold anyone up and accelerating with traffic frequently pushes the display into the “red” zone. Morning temperatures ~50-60F, A/C on ~ 80% of the time, original tires inflated ~ 2-3lb over the sticker, regular gas (Top Tier), no roof rack.

80% of fuel economy is dictated by the driver. If you are a short sighted, pedal-pumping, surge type of driver, your mileage will be far less than a far-looking, smooth, anticipative driver.

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I would guess that only 50 % get the advertised miles per gallon .

Are you measuring the fuel economy at the pump and with your miles, or are you relying on the car’s average display. Just curious.

Are you having cold weather? That cuts mpgs.

What is the advertised mpg?

I think @KeithClement has a heavy right foot, as my old Gen2 Prius easily gets 48-49 MPG with my wife’ driving, she tends to push accelerator more, I’m getting 50+ from this old beater.

Yes, a lot of factors can be taken into consideration. I bought the vehicle in Baton Rouge and drove to Oregon - 2200 miles of highway driving. MPG ranged from 44 to 48. Now, my wife drives about 30 miles a day, highway and city, and gets about 46. Our old 2010 Prius got 49 mpg consistently. It seems like we should be doing better with the new vehicle,

Car display.

advertised is 54.

With our 2010 Prius we got 49, so I think it is not our driving. The latest generation Prius advertise better MPG.

Faulty engine thermostat is a common cause of reduced mpg. The engine has to be running at the designed temperature to be maximally efficient. If I had that problem I’d do a round trip, bring along my pocket calculator, fill the tank, then take the car on a mostly level freeway route on a day there’s little to no wind, and drive at a constant speed, one I’d expect good mpg, say 55 mph. 100-200 miles later, preferably using the same gas station and pump I’d previously used, fill the tank again. mpg = elapsed miles/gallons used.

Until you check your miles per gallon the old fashioned way you can’t really know what you are getting . The dash readout is not done by NASA grade instruments . Plus the fuel mixture might be different in Oregon as compared to Baton Rouge .

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Our 2012 got 52mpg going 30 mi to work at 55mph. I got 35mpg at 75mph on a trip thru Montana. That was speed limit. Prius does not like speeds >65mph for good mileage. I would say our 2012 is old vs a 2019. Maybe new ones like high speeds?

Lots of differences between Baton Rouge and Oregon. Any hills on your new commute? Colder temps? Both can make a big difference.

I noticed on my 2200 mile trip it definitely did better when I dropped from 75 to 65.

Agreed, it doesn’t seem right for a new Gen 4 Prius to get lower mileage than a Gen 3 under similar service. One presumes you’re comparing actual consumption at the gas pump over a number of fill ups and not the dashboard number which can be inaccurate. Have you confirmed that the traction battery air intake and the filter behind it aren’t blocked (on Gen 4 this is inside the car, under the rear passenger’s seat, facing forward).

Your next move might be to take it up with Toyota, they should know what to check and may have service bulletins on this problem. Among things for them to explore are whether the traction battery is up to snuff and if the computer codes are correct and up to date. If they try to tell you that EPA is an estimate and “your mileage may vary”, keep reminding them that your Gen 3 does better. Be prepared to do a deep dive with them, involving the regional service manager, etc.

While you’re seeing a 13% difference in mileage (46mpg vs. the combined EPA 52mpg), in absolute consumption terms this is 0.25 gal/100 miles, so the inefficiencies responsible are relatively small and may be difficult to identify.

I would first check to see if the tires are inflated to the specified pressure posted on the left door pillar.
Also, as noted, weather conditions make a difference. Gasoline is also blended differently for different seasons and different regions of the country.
I only use the mpg display as a rough guide as to the condition of the engine. When I really want to know the exact mpg, I calculate the mileage over a distance of at least 300 miles by the number of gallons used.
The first vehicle I owned with a mpg display was a 1990 Ford Aerostar Eddie Bauer edition. I wanted to disable the display. Our son was a teenage driver and he could get better gas mileage than anyone else in the family. He has always been an easy going person and it is reflected in his driving. He could have been a great driver on the old Mobilgas Economy Run in the 1950s.