Colder weather has zapped my mileage to 44mpg

And we're off-topic yet again...

Regarding the question of lower Prius mileage in the cold, I think we've mostly answered the question as far as high-speed driving goes: aerodynamics (denser air) and possibly/probably also rolling resistance. The combination of the two is likely pushing the engine a little outside the sweet spot, and this is more significant/dramatic at higher speeds (especially >70mph).

But there's also a MPG drop affecting lower speeds (any speeds), even when all factors other than temp are the same - and at those speeds, aerodynamics and rolling resistance are far less significant. Grill blocking helps a little in the first few miles, but doesn't seem to make much difference after that. The one thread I read about someone trying 100%/100% blocking led to engine stutter.

Is it possibly the cold battery that makes the difference? I'm tempted to crank the cabin heat all the way up to see if that helps at all, although obviously that will cause losses also...

I'm not complaining about the MPG I'm getting - but IF it's possible to do a little better, I'd like to figure out how.

 

Well, I care... mostly because that's a $1400 option . And that's just an initial cost, slapping new rubber on an 18 vs a 15 is one heck of a difference. Color me strange, but, I don't get the allure of larger wheels to a car, the price of the rubber being one. The additional hit to spool them up being another. So, do they offer anything more than looks?

But hey, that's just me. Cars stopped being more than transportation about 3 kids ago, and on top of that I'm a cheap bastard . I really didn't want to spend more than 12k on my next car considering the amount of miles I stack up a year, but getting a lower mileage used Prius required going into the 15-16k range.

 

I already have 16K in my Prius... I'm also a cheap bastard , but when you drive that much and spend part of your life inside a car, better be happy with it.

 

And we're off-topic yet again...

Regarding the question of lower Prius mileage in the cold, I think we've mostly answered the question as far as high-speed driving goes: aerodynamics (denser air) and possibly/probably also rolling resistance. The combination of the two is likely pushing the engine a little outside the sweet spot, and this is more significant/dramatic at higher speeds (especially >70mph).

But there's also a MPG drop affecting lower speeds (any speeds), even when all factors other than temp are the same - and at those speeds, aerodynamics and rolling resistance are far less significant. Grill blocking helps a little in the first few miles, but doesn't seem to make much difference after that. The one thread I read about someone trying 100%/100% blocking led to engine stutter.

Is it possibly the cold battery that makes the difference? I'm tempted to crank the cabin heat all the way up to see if that helps at all, although obviously that will cause losses also...

 

Yes, my driving this week has been city driving (34 MPH) at very good road conditions (low speeds with few stops) for FE, the same drive where I used to get 64 MPG (MID) back on summer... so far I'm getting 50 (MID) and it has been upper 20's and lower 30"s F around here. So the drop is still impressive 21.8%, even at lower speeds with blocked grille...

 

Yeah, winter is a pain for fuel economy. I'm getting the same 20% drop in my city driving, only a 65MPG this morning, same temps and average speed as you. Sigh.

Wayne

 

I was stuck in the 50's mpg in my city driving this morning, since I couldn't get my engine heat over 156F to glide. It's almost enough to send me to get some more radiator blocking stuff for 50% of the bottom grill.

 

My 2005 dips into the lo-mid 30s in the winter (this winter seems the worst so far) - I am led to believe it is a combination of winter fuel, short runs (my commute is ~15 miles), cold weather, and in my case, hilly terrain. My summer mpg on the same commute is closer to 45. Highway driving, even in the winter, is close to 50. I've learned tp live with it; still better than everything else.

John

 

Sague, maybe you don't know but when Wayne says he is getting 20% drop and still getting 65, he's not kidding! He's the master of FE... I think his commute is perfect for it too...

 

Don't take me wrong but there is more than a handful of cars than can do low 30's MPG on winter...

 

And a whole lot of cars that can't get to 30 on a perfect day.

Tom

 

The less efficient car also costs more, has almost certainly inferior reliability, higher average per gallon fuel costs and higher maintenance costs.

 

If those features are so important to you, why didn't you go for the Prius V? Seriously, you're trying too hard to justify your desire for the Audi. We don't really care, it's your wife that needs the convincing, I think!

 

I agree with your post.

Yes. I drove an Audi TT - I have a friend who owns one. They are not as reliable as Toyota and I think many surveys have stated that. I wouldn't buy an Audi but if FE is not the poster's most important concern, then something a little more sporty of course, will fit better.

High on my list of concerns is reliability. For the Prius, I wanted economy. Toyota delivers very well.

By the way, it warmed up in Virginia today and I am at 52 mpg as indicated by the Toyota display. I understand the display is optimistic but I use it more as a comparative measurement to compare winter vs. summer mileage.

 

True although it goes totally out of question here, doesn't it?

 

Again, a very small price for decent acceleration, comfortable seats, solid interior, more intelligent and intuitive controls, more space for my knees, quieter ride, better handling, and mostly important… the A3 is a car that actually feels like a car.

I may even consider change my Prius to a Jetta SGW TDI and spend nothing in the trade. The SGW would have similar attributes and more cargo room compared to the Prius, but the down side of that is, quoting an Audi dealer, “the new Jetta interior got a little bit “Toyotasizedâ€â€¦â€

Have I told you that I have tried 4 different lumbar support devices in my Prius and none seems to help? My doctor said the only solution is actually changing the whole seat… That cost is in the equation too…

 

Here in New England tdi fuel is @ 3.10 per gal. Gas is 2.65. I had a TDI and the fuel consumption in town is awful. On the freeway normal driving was 42 -44 on a good day. It took for ever( 7-8 miles) to warm up and get some heat. The electric seat heaters would overheat and there was a recall because of the danger of fire.

I think you would be happier with a V.

 

Maybe a tiny handfull; My prius replaced a honda civic which was (and still is)one of the best in mileage; it would get maybe 40 mpg tops on the highway, but on the same commute, in winter, it would drop to the upper 20s. So I'm quite pleased with my Prius results, but wish I could do better in winter. I have NOT been blocking the grille, though, and will try that.

John

 

Prius V? Are you kidding me? The only thing that would be better in that case was seat comfort, nothing else! How different is a Prius III from a V based on my needs? Same bloody HSD (which makes you forget about what driving I real car should look like and forces you drive it like your playing a video game), same winter MPG Drop, same drop at minimal adverse conditions, same interior full of rattles and creaks, same cramped knee room because of the gigantic center console, same struggling to keep the car on the lane over 70 MPH, same "must do tricks" for better FE in winter...etc, etc, etc...

Talking about buyers remorse... I actually wished I had bought Prius V instead of III, so now I could trade it for a loaded A3 TDI with minimal, if any, additional cost!

It’s a no-brainer that older Prius has better reliability ratings compared to older A3s or older Jettas. I’m not fighting that! But do you also know that VW/Audi of America is providing free maintenance up to 36K miles? I think their factory warranty has also being extended recently. Also, we don’t know how reliable the new Jettas and A3 TDIs are until 3 years from now and same for the Prius. Supposedly, VW/Audi is getting better just like Ford and Hyundai. As reliability slowly changes… the whole game changes too… We all know what happened to a big car company that started going downhill several years ago because they were more worried about boosting up their production and forgot about quality standards, don’t we?