New to Prius: Can't achieve above 45 MPG

Let the Prius glide, that's the best way to achieve high mpg. Gliding is mainly used at low speed (below 40 mph). But I also glide on the freeways as well. If you don't know what I'm talking about, go to youtube and search for "Prius Pulse and Glide"

 

Yes, 45 mpg is sort of a surprise. The only time my Prius ever got that low was the time I let my son drive. He was doing 75 mph on the freeway non-stop for 60 miles. During that trip, our elevation also increased by 500 ft, my GPS said that we did.

I personally never have gotten that low once the Prius is warmed up.

PS: Check your tire pressure. I set mine to 40 psi

 

Checking against my baseline, benchmark:

At "78 mph" 45 MPG is right, there is no problem. To reduce your MPG at 78 mph requires aerodynamic modifications or if MPG is important, a lower speed.

You might consider setting the cruise control to 65-70 mph and getting 50-55 MPG. Bring good music and enjoy the ride. If there are semi-trailer trucks on the route, use them as pacing vehicles and no one will notice 'the Prius stuck behind the truck.'

Aerodynamic modifications are a little more involved than a single post reply. Testing reduced cooling drag, I've gotten about a 4% reduction, 52 MPG -> 54 MPG. Using more sophisticated modifications, I would not expect no more than a 10% improvement.

Bob Wilson

 

Worth noting I'm religious about cruise control, even in town



Cruse control in city traffic is counter productive and possibly dangerous.

 

Short trips pay a heavy 'warm-up' cost. Also, route planning is important. So let me suggest a couple of things:

• Reset trip meter -> start car -> let it auto-stop . . . about 1-2 minutes :: this handles the initial catalytic converter warm-up, the inefficient "closed-loop" part of warm-up. You can use this time to fasten seat belt, check mirrors and seat, and tune radio/music.
• Choose slowest route for first 1-2 miles :: this lets the engine coolant warm up under minimum load while cutting through the neighborhood which is often posted at 25 mph.
• Drive on cruise control while monitoring the energy flow:
  • if energy flows from wheels to traction battery - shift into "N"
  • if in "N" and speed falls to cruise control speed - shift into "D" and hit "resume"
  • coming to a stop, be sure to shift into "D"

If you would share a Google Map of the Starbucks route, we could go over options.

Bob Wilson

 

This morning I drove my first 10 miles of the day and I got 62 mpg. I had to deal with stop signs and lights. Speed limits were 15/35/45. Do you have the "ECO" mode turned on? I don't use cruise control. I know your trip was only 6 miles but you should still get over 50 mpg

 

Are you on the original tank of gas?

Prius chat get's these type of early owner posts rather frequently.

You can try all the suggestions in regards to maintenance and driving style application and they may help...or they WILL help.

But my suggestion is simply don't panic. Learn how to read, and reset your gauges. Make MPG calculations based on actual pump/ mileage data.

And wait until your sample size of feedback is more than 1 tank and less than a 1000 miles driven.

Once you driven a few tanks...and have some real mileage on the vehicle, and you are sure of the mileage you are getting, THEN you can determine if you really should be concerned.

I do a lot of short trip....to work. So I know I pay a penalty. I'm still getting 45-50+ mpg, and I'm very happy with that. But my gas mileage is usually boosted on the weekends when I'm more likely to drive longer and further. So I guess my repeated point is you just need a bigger sample size of driving.

If I had just got my Prius, and was judging from MPG initially from my short trips, I'd probably be upset. But it's really full tanks, and multiple tanks that will give you a better idea of what your real overall MPG average is.

 

sounds like a lemon, i've never gotten less than 50, short or long trips unless the temps are well below freezing. how does your wife do, same thing?

 

agreed. hopefully, some here will be able to help you figure it out. try filling out the 'why are my mpg's so low' survey, it might give us a clue. all the best!

 

I'm glad I didn't give in and buy the Jetta/Passat diesel before I bought the v. The torque of the diesel is so alluring when accelerating or pulling away from a standstill that I likely couldn't resist it, and there would go my mileage. At least around town....

 

Have you ever mashed on the pedal at a stop light in your v? With a full battery, there's considerable torque available.

 

I've been thinking about this too:

You have no problem:

• 42 MPG / 30 MPG = 140% better than your last car

The Prius is beating the pants off of what you used to drive but you are complaining like my wife. When my wife is unhappy with something, she poses the question:

"Why didn't you do <something she is unhappy about.>​

The whole premise of this thread started with questioning why your Prius . . . in your hands . . . is not achieving performance similar to what the rest of us think is trivial . . . and not just us. From Fuelly - Track and Compare Your MPG:

• 48.2 MPG average - 204 cars, 2013 Prius
• 48.4 MPG average - 470 cars, 2012 Prius
• 48.4 MPG average - 308 cars, 2011 Prius

But you gave a valuable clue, ". . . excellent hypermiler . . ." so I'm going to suggest return to:

CleanMPG, An authoritative source on fuel economy and hypermiling​

They have a vested interest in seeing that "hypermiling" works. You've come here and even though claiming great skills and getting 140% of your earlier MPG, you are still disappointed. I don't know about anyone else but I am pretty sure I can't help you achieve what an EPA government bureaucrat can accomplish seven days a week and twice on Sunday. In short, I am sure there is no dialog going on and the clues suggests you came here, like my wife's style of criticism, to ask a rhetorical question . . . not diagnose the 'nut behind the wheel.'

This is enough noise in the world that we sometimes have to mute the radio. In this case, turn off following the thread. Of course some of our Prius brethren may speak a variant that you understand . . . or not. I just have something else to do.

GOOD LUCK!
Bob Wilson