Picked up second two eco - gas mileage not as good as first

congrats! 'his' still on the dealer tank?

 

Is the MPG measured by a fill up, or is it just the dash read out. Don't expect the read out to be adjusted the same.

Take a look at the tires. The more wear on them, the lower the rolling resistance is to be expected, but make sure they are at the same pressures, and even brand. Also check the oil level.

Other than that, just give it some more time. I give them until a 1000 miles before I'd start considering any major issues.

 

you gotta me sure the second fill up to be sure.

 

here is the Gen 3 form for getting good answers on MPG, I hope it works as well for gen 4

Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat

 

Different driving habits should also be considered.

 

good idea on the tyre s pressure and oil, you never know. are they the exact same tyres? some have been reporting odd model numbers i think.

 

My experience with a non-Prius is that if I say ½ fill the tank, the dashboard readout won't be as accurate as if it's taken to the first click. Even if it came with a "full tank", the dealer might have been a little approximate with their fill. The dashboard readout is often a good indication, but isn't accurate enough for conclusive comparisons.

The only way to compare properly would be to fill both tanks to the same extent (ie first click of bowser), same bowser, same position parked while filling. Then drive both for the same distance and re-top the tanks. THEN, do the same thing, but swap driver - you could be amazed by the difference that makes. It could be driving style - or the amount of stuff you take with you compared with what she has in her car. Or even your own mass compared with your wife's mass. It could even be that you drive the same route ½ hr later every day when the traffic is more conducive to what a Prius would like.

Best way to do it is to keep a spreadsheet on fuel use - I've done that for the last 26 years, and it produces some interesting results.

 

agreed, the more tank average's the better. bowser's can be finicky.

 

You're having second thoughts on the car even though you're getting a minimum 53mpg? You won't find 2 cars that will be identical, it will always vary by a little.

You definitely should let both cars completely break in before doing any comparisons. Maybe after 1000 miles on the clock

 

Don't discount the impact of even 5* in the outside air temperature on the day it is driven, either.

Especially for the first 5 or 10 miles after startup (or so it seems).

At my latitude, the temperature swings have been significant and almost random.

 

The factory fill may have been done by weight. It should be the same level between the cars, but you never really know, and it is something easy to check.

Outside temperatures influence a number of things that can influence fuel economy. Tire pressure and rubber flexibility change with temperature. Then the grease in wheel bearings and CV joints need to warm up without the help of ICE heat. Just to name a couple.

 

Not sure what happened, but the first fill up of my TWO Eco, the dash display claimed 77mpg when the pencil and calculator said it was 61.x mpg.
The following three fill ups have the dash display claiming 1.5 - 2% optimistic.

 

has to be where the pump shut off. it doesn't take much to change the equation significantly.

 

You might have a lead foot. I do