2011 gas economy worst than old 2006 Prius

I'd blame it on weather first. I'm on my third winter with my 2011...in previous two winters, my MPG has been in the low 40s. With this winter's brutal temperatures, my Prius is barely getting into the upper 30s. Also check tires...are you running on LRRs? And remember as temperatures drop, so does air pressure in tires.

 

Does the 2011 have the stock OEM LRR 15" tires or has someone replaced them with conventional tires?
Gen III likes overinflated (as compared to Toyota's recommendations) tires- try 38psi front 40psi rear, or even 40 front 42 rear...

 

Low rolling resistance tire.

 

WRONG!
The power zone is the extreme right and not past midpoint.
What you do, you force too much EV driving causing:
1. enraged fellow drivers behind you
2. depleted HV battery and decreased MPG
3. wear and tear on HV and early failure
4. did I mention enraged fellow drivers behind you?

You have to learn how to pulse and glide.

 

IABoy987, I'm sorry for your loss but the 1.8l engine can't be blamed. Tires make a big difference. My 2010 on 17" wheels was marginally better than my 2006 on 15" wheels when both cars had Low Rolling Resistance tires. My replacement tire choice on the 2010 resulted in a ~10% hit to the fuel economy.

Tire pressure also makes a difference. Do you really want to run with 34psi in a tire designed for 51psi?

The bigger problem was--me. My 2010 is not a Gen 2. It is not full of Gen 2 parts. I can't drive it like a Gen 2 and get the same numbers. The transition points are different. The feel is different. I had to adjust (not unlearn) everything I did and it took time.

Staying on the left side of the bar is killing you. When the car's hot and the battery is full staying there will get you fantastic numbers--for a mile, maybe two. Then those numbers evaporate as the ICE kicks in to recharge the battery.

I suggest get up to speed quickly but don't go in to the far right red zone as that is very inefficient. Once there, foot off the gas all the way just for a second then bring the power back up staying on the left side or going over if you need to.

If you just reduce pressure on the pedal you'll drop into the left side of the bar but the throttle stays open resulting in pretty disappointing instantaneous fuel economy (as reported by ScanGauge).

I'd say the Gen3 is programmed so that it is easier to get a good number and it is more consistent. The Gen2 took more work to get a good number and it could post some great numbers on occasion.

If the 12v battery is weak the traction battery will be working harder trying to get it charged or keep it charged. That'll get the ICE to run more than it should.

Unless there's evidence that something needs to be replaced (hopefully under warranty) taking it back to the dealer is just going to be a waste of your money & everyone's time as they just say everything's fine.

I feel your pain & frustration as I've been there.

 

And my experience found that use of any oil other than the expensive 0w20 recommended oil, caused a drop in fuel economy and performance. With 5w20 I couldn't get an average over 59mpg (UK) but with 0w20 I could run at 75+ mpg (UK).


ps (our gallons are bigger, so 50 mpg UK is about 41 mpg USA)

 

Just a suggestion, you might copy and answer the mileage checklist:
Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat

There are many things that can lead to low MPG ranging from vehicle maintenance, tires, terrain, and driving. My interest has been in warm-up practices and route planning. So my interest is in the first 1-2 miles and how the car is started in the morning.

Bob Wilson

 

I find that I get the best mileage when I keep the battery around 60 % charge and simply use the ice when I need it. When cruising on a level road, I back the throttle off to the left of the mid mark on the indicator such that the ice remains running at idle (near 960rpm). The instant mileage meter hovers between 70 - 80 this way. I then back off when I need to glide or when I see a red light ahead. In the summer, I routinely get high fifties low sixties in mileage. In the winter, mid fifties (in Alabama). What they say about the battery is true. All energy comes from the ice. Converting to electric energy for storage is not efficient. The best use of the battery is for energy RECOVERY-when you glide, stop, or go down hills. Anything accumulated over 60% charge is gravy and can then be used to reduce the load on the ice or to goose the car along on a stretch of road without using the ice. I keep the battery load about 20 amps (ish) when doing this. I use a scangauge to monitor these numbers, which is helpful, but you don't have to have it to use these techniques.

 

You got to drive past midpoint AS MUCH AS POSSIBLE, not as little as possible. Only the extreme right little piece is the power zone. the rest of the right side is the ECO zone. You have been driving totally wrong.

 

good point cary. o/p, if you're trying to keep the bar from going past the midpoint, you're driving in ev too much and this will kill your mpg's. accellerate with the bar just to the right of midpoint until you reach speed, then glide with bar just to right of regen.

 

35 is way too low. Your efforts at "trying", may be hurting the result. Read up on hypermiling the Gen III. That should help.

 

Well if I can be as bold as to make a few assumptions here...

Since the OP's profile say's member since 2011...and they owned a Prius previous to this one, I'm going to say whatever that it's NOT differences in how they are driving the new Prius.

They've owned a Prius for several years. Maybe they could use some tips on more efficient driving, but it shouldn't really explain a huge or significant difference or drop between the two Prius because I assume they drove the previous Prius, just as they are driving this one.

This is all in comparison to the Prius they owned before.

If your mileage for the same time of year, is falling that far below what you used to get? I'd say you might have a problem somewhere.

And no, IMO it doesn't have anything to do with the engine size difference between the generations. While the engine size did increase in the Gen 3, gas mileage was actually marginally improved. Parts of the HSD system were made smaller and lighter.

I know at the time of release, it was presented that the larger 4 cylinder engine would offer the Prius a quieter, smoother, more powerful and efficient highway driving experience. But gas mileage was not negatively affected.

 

if they are driving the new Prius the same as the drove the old Prius, he sure didn't describe it properly in his initial post. I think you are too bold to state that.

 

agree with cary again. in the gen II, there is no power bar, so it's more difficult to stay in ev on accelleration. we could be wrong about this, but won't know until op comes back to reply.

 

Yes, take it toyota, as you got 40's with a gen2, you should get 50's with a gen 3, but the question was asked, 15" or 17" wheels?(didn't see it answered)
My gen2 got 30's for mileage when it had a bad spark plug. Here in jan, in nh I'm getting 51.5mpg's, gen 3, and holding steady.(with 15" studded nokians)

 

Uh Oh! Another '23 post wonder where they went?'

Bob Wilson