Poor Yaris Hybrid Mpg?

[Ethanedwards]

Well I run mine all through the winter. Cold weather means I lose up to 5mpg but that's really cold weather. Summer I average 58-62ish best ever 67. It's really a very different driving style from a turbo diesel. Steady speed. Lots of anticipation keep rolling while you can, keepvthe tyre pressures checked etc. Pulse and glide when you can. Really driving like you stole it gives me exactly the mpg your getting. So maybe try being a bit less leaden in driving style?

[Cyker]

It's all about the acceleration part; With diesels it's better to accelerate a bit more briskly, as they are far more efficient under load than petrols, and climb the gears, then abuse the low-end torque you get with diesel to let it run barely above idle in the highest gear you can get away with without straining the engine.

HSD owners have said you can do a similar thing with HSD's as the electric motor provides most of the torque, then you can let the engine relax and the atkinson-cycle IC engine can take over just keeping the car rolling. The atkinson engine has near-diesel efficiency so this should work pretty well. The main issue is although the atkinson engine is very efficient, it has very little torque so it has to run at a relatively higher RPM to keep the car going if there's no electric motor assistance, and I suspect this is why some people are finding they get lower than expected mpg on long motorway runs whereas diesels tend to be a lot more consistent.

The winter running of the HSD is not bad tho' - Diesels get hit worse! Worst-case example: During the snow times last year, my dad (Who mostly uses it for short journeys nowadays) was getting something stupid like 135 miles out of a tank that could get over 700 in summer during long motorway runs!!!

[johalareewi]

Lots of reasons for poor hybrid mpgs.

Winter, low tyre pressures, non LRR tyres, wrong engine oil, driving style, etc.

A couple of these shouldn't apply to a new car but the others will ;)

[Joseph D]

Lots of reasons for poor hybrid mpgs.

Winter, low tyre pressures, non LRR tyres, wrong engine oil, driving style, etc.

A couple of these shouldn't apply to a new car but the others will ;)

I second this. :)

[GSC112]

In reply to GC I reguaraly do the same journeys in the Mercedes I owned from new until it was 4 years old I found that the mileage improved a lot after it had done about 18000 miles, The mpg figures quoted were not instantanious figures but over whole tank fulls and readings calculated by using total mileage and pump readings taken when refilling. THe mercedes average for combined mileage was nearly exact or slightly better than Mercedes quoted. The Yaris combined readings over nearly exactly the same runs ie Nwales -Exeter and weekend aways from home to a caravan site virtually weekly, means that I can quote comparisons. I find that the yaris is about a third less that the combined figures that Toyota quote.

I don't expect any way that I will ever achieve mpg figures in the 70s, but I would at least like them to start with a 6 or be in the top 50s not nearly always in the 40/50 mark.

ps I check my tyres on a regular basis as I had a blowout once and after serious injuries and six month recovery time. (you can say I was ocd over tyres)

[Grumpy Cabbie]

Then you have a faulty car. There is no way the Mercedes will get 55 mpg and the Yaris HSD only get 50 mpg over the same route unless the car is faulty or the goal posts have changed, or you're using the car for something it wasn't designed for. Having driven lots of Mercedes over many years I know they'll happily sit on the motorway at 100 mph like it's a walk in the park for them. Try that in a Yaris HSD and you will get poor economy.

But there have been a number of reports of the Yaris HSD not getting the economy of the much larger Prius. I wonder if the li-ion Battery isn't all it's cracked up to be, or maybe being designed away from Toyota Japan who have over a decade of hybrid design, the European arm just can't master it? Remember the trouble with the new Auris HSD?

To confirm. If my Prius gets less than 45 mpg after I've hammered it (and I mean driven hard), then there's something wrong. It will get 50-60 mpg in very short runs in traffic (50 in winter with heater on, 60 in summer with a/c). On a motorway run at 80 mph, you'll get 55-65 mpg. At 50 mph on the flat I'll get 65-80 mpg (not tank average, but trip average - cold starts do affect it). I have often got 70 mpg with ease over a distance of 20+ miles as anything less is just irrelevant. I have even got 90+ mpg over 20 miles taking it very easy (wouldn't recommend it as you'd die of boredom).

GSC112, Double check your tyres as even 1 or 2 psi below recommended makes a difference. Is your tracking spot on? I know dealers are meant to check it before releasing the car, but few appear to do so. That can make a difference. Try not to over-ride the hybrid system by trying to keep the car in electric etc. Just drive steady and let the car work itself out.

[timberwolf]

https://www.fuelly.com/driver/grumpycabbie/prius/log/page/4

December 5, 2009

Ave Speed 12 mph

• 92.0

  Miles

• 10.01

  Litres

• £1.089

  Price/Litre

• £10.90

  Total

• 41.8

  UK MPG

added by GrumpyCabbie on December 5 at 10:36 am

November 27, 2009

Ave Speed 10 mph! Night Shift

• 96.0

  Miles

• 10.10

  Litres

• £1.069

  Price/Litre

• £10.80

  Total

• 43.2

  UK MPG

added by GrumpyCabbie on November 28 at 3:45 am

[Cyker]

Yeah, the HSDs are not designed for high-speed cruising - If you really want to get good mpgs, find the sweet-spot speed - In most cars it's around the low-mid 60's - where the engine can push the car along with minimal energy input and stick to it.

With mine, I know I have to keep the RPMs below the turbo threshold to get the best mpgs, no matter what speed I'm doing.

In the HSD, you have all these funky energy meters so take a glance now and then and see what pedal pressure and speeds seem to yield the best mpg for you :)

I'd recommend jacking up the tyre pressures by a few PSI too - Somewhere between 35 and 40psi is generally optimal. It makes a noticeable difference if you're mostly doing motorway runs. You can really feel the extra roll distance when you lift off :D (Just don't roll into the back of someone! )

[Grumpy Cabbie]

And if you note the comments in those sections you will see that it was very cold here in North Yorkshire on those TWO days and that I left the car running to keep warm :)

My averages were often per day in the early stages before I ran the tank from full to empty.

If you're sat in an empty car park at -5c for 10 hours a day inbetween jobs, you'll leave the car running for heat too.

But even then, let's just think about this. I got 41.8 mpg over 92 miles at an average speed of 12 mph. Is that bad? I'd love to see what a Mercedes would get in those conditions.

[Cyker]

At that speed the cold temp light on my Yaris would never go out in winter!

[timberwolf]

I picked those figures because they were the lowest and I imagined even a taxi driver couldn't drive with a heavy right foot when they were parked!? It would seem to demonstrate how much fuel can be used when it is cold just to keep the engine, catalytic converters and cabin warm.

All four pages of your fuelly, approximately +100 entries, shows a striking difference between tankful-to-tankful calculation of mpg, and the mpg figures estimated and posted here by members based on what their car's onboard computer showed.

As has been said before, if anyone wants real world mpg they would be better served by looking at fuelly or honestjohn.

[Grumpy Cabbie]

But taxi use is completely different to commuters. 10 hours + a day in traffic, racing to a job, driving steadily with passengers, idling in traffic lights, idling outside their house for 10 minutes whilst they faff about. There is much idling to be had in taxi work. That's why the economy is right down and why I got a Prius.

Then there are gaps in the quiet periods where you switch the car off and it cools down, then after an hour you start up and idle away again.

But the fuelly stats are actual calculations, not the slightly optimistic readings from the car (which is usually 2 mpg over). So I appreciate your reasons for posting those two ratings. They were when the car was less than 6 weeks old, running hard taxi miles in November/December at an average speed of 10-12 mph. The lowest mpg was just shy of 42 mpg.

Impossible in a Mercedes diesel and many of my taxi colleagues has C and E and even S class diesels and they got below 30 mpg in town and scraped low 40's on a run.

[GSC112]

Thank you for your reply I calculate my mpg using 4.54609 litres per gallon and actual mileage from oddometer also if I use the computer figures they are slighly better than my own .

if you want to be really technical, check you speedo against a satnav at a constant speed and see also how far out the readings are. (ps I am a Metering engineer who calculates Oil and gas flows and quantities for a living! )

I am know my readings are correct and all readings are combined figures over whole tank fulls. the Mercedes was about 10% lower until it bedded in the Yaris is about 25% lower than Toyotas listed combined figures.

I always run tyres slightly hard as any Mercedes vowner would know otherwise the front tyres last no time

[Grumpy Cabbie]

Other have found similar, but mine didn't fully bed in and get its best average mpg's until around 5,000-10,000 miles.

See how you go with the Yaris HSD which is a little different to the Prius.

[orangezorki]

I'm nearing the end of what I think is my fourth tank of fuel, and I'm getting just over 55mpg - that is with the few days of gridlock in London with the tube strike last week. Admittedly, I have been very careful (P&G, no aircon, ECO mode etc), and the car has only done a bit more that 1000 miles, but I don't think that's too bad.

David

[Grumpy Cabbie]

Personally I think way too much is made of Pulse and Glide and unless it's done correctly it's counter productive.

P&G is used by serious hypermilers in the US who can get over 90+ mpg out of a Prius. Getting 55 out of a Yaris that is rated at 70+ is not in the same ballpark. You'd be best just driving gently and letting the car do the thinking. I gave P&G a pop and yes you can get good mpg's (when I got 91 mpg over 20 miles) but you'd die of boredom OR a roadrage attack lol.

I drove to Battersea the other year from Yorkshire. It was 80 (Car reading = 72 actual) down the motorways, 2 hours crawling into central London, park up, enjoy crap day out at EcoVelocity, spend 2 hours getting out of London and driving back up north at 80. I got 57 mpg that day without trying with heating and a/c on.

It has been mentioned before on here and other forums but I'll reiterate it (in a nice way without trying to sound like a forum bore). Just let the hybrid car sort itself out. It does a cracking job. Toyota have spent 14 years perfecting it. A mistake a lot of newbie owners (me included at the time) is to try and out smart the car to get better mpgs. Generally over the long term you won't. I know it's addictive to drive on electric and watch your mpg's read 100+mpg for a few miles but eventually the car has to top up the Battery more than it would have and will use more fuel trying.

Just ask the older members on here who will agree - I think :)

[Joseph D]

Personally I think way too much is made of Pulse and Glide and unless it's done correctly it's counter productive.

P&G is used by serious hypermilers in the US who can get over 90+ mpg out of a Prius. Getting 55 out of a Yaris that is rated at 70+ is not in the same ballpark. You'd be best just driving gently and letting the car do the thinking. I gave P&G a pop and yes you can get good mpg's (when I got 91 mpg over 20 miles) but you'd die of boredom OR a roadrage attack lol. ...

My take on P&G is not try to do it all the time, but rather do it where you can. You need to have the right environment so that you don't put yourself at risk of road rage. And it needn't be boring.

Another variation on pulse & glide is to just gliding where you can. I have a considerable stretch that is slightly down hill and I make sure to get in the glide to take maximum advantage of it.

It has been mentioned before on here and other forums but I'll reiterate it (in a nice way without trying to sound like a forum bore). Just let the hybrid car sort itself out. It does a cracking job. Toyota have spent 14 years perfecting it. A mistake a lot of newbie owners (me included at the time) is to try and out smart the car to get better mpgs. Generally over the long term you won't. I know it's addictive to drive on electric and watch your mpg's read 100+mpg for a few miles but eventually the car has to top up the battery more than it would have and will use more fuel trying. ...

I agree 100% with this sentiment, and have said it many times myself. If you focus more on lifetime average MPG and tankful averages, rather than short trip MPG's, you will develop habits that work long term, which is to your advantage.

[Cyker]

IMHO Pulse/gliding is only something you can really use at higher speeds and I think it's more useful for us pure IC people than the HSD's.

With HSDs is probably best to NOT come off the throttle completely, but find that point on the accelerator where the car can effectively roll as if it's in neutral, without any engine braking but without putting any power in. You don't recover any energy that way, but it's far more efficient to maintain your rolling momentum than letting the HSD sap your kinetic energy only to feed it back into the wheels again.

Personally, I reckon my biggest savings in town are resisting the temptation to accelerate at the same speed as the car in front in stop-start traffic, but instead accelerate slightly slower so a buffer gap starts to build. It takes some practice at anticipation, but on regular commute routes that I know well, I can often roll right through the traffic jam with only one or two stops, while everyone else is THROTTLE! BRAKE! THROTTLE! BRAKE! all the way through.

You do have to be very aware of asshats who will try and cut in if it's a multi-lane road, but if you stay on the left, most people would rather stay in their middle/far-lane log-jam than come in for some reason!
(Seriously, why is this? Last weekend, big jam on M1 but I was in the left lane and had over 200m of clear space in front and behind me in the left lane! I didn't even try to race to close it, was just letting the car decelerate by itself from 60 to whatever and never even had to stop, just dropped it into 3rd and let the idle tickover pull me along at ~13mph behind an Eddie Stobart while the other two lanes had stopped!)

[Joseph D]

IMHO Pulse/gliding is only something you can really use at higher speeds and I think it's more useful for us pure IC people than the HSD's.

But in the HSD it is best up to 40 mph.

With HSDs is probably best to NOT come off the throttle completely, but find that point on the accelerator where the car can effectively roll as if it's in neutral, without any engine braking but without putting any power in.

This is exactly the technique for gliding in the HSD.

You don't recover any energy that way, but it's far more efficient to maintain your rolling momentum than letting the HSD sap your kinetic energy only to feed it back into the wheels again.

Exactly.

Personally, I reckon my biggest savings in town are resisting the temptation to accelerate at the same speed as the car in front in stop-start traffic, but instead accelerate slightly slower so a buffer gap starts to build. It takes some practice at anticipation, but on regular commute routes that I know well, I can often roll right through the traffic jam with only one or two stops, while everyone else is THROTTLE! BRAKE! THROTTLE! BRAKE! all the way through.

You do have to be very aware of asshats who will try and cut in if it's a multi-lane road, but if you stay on the left, most people would rather stay in their middle/far-lane log-jam than come in for some reason!

This is the same technique for the HSD.

(Seriously, why is this? Last weekend, big jam on M1 but I was in the left lane and had over 200m of clear space in front and behind me in the left lane! I didn't even try to race to close it, was just letting the car decelerate by itself from 60 to whatever and never even had to stop, just dropped it into 3rd and let the idle tickover pull me along at ~13mph behind an Eddie Stobart while the other two lanes had stopped!)

The left lane is the slow lane reserved for HGV's and must not, under any circumstances, be used by motor vehicles. I don't care too much as I do the same as you. Much less stressful.

[orangezorki]

Personally I think way too much is made of Pulse and Glide and unless it's done correctly it's counter productive.

P&G is used by serious hypermilers in the US who can get over 90+ mpg out of a Prius. Getting 55 out of a Yaris that is rated at 70+ is not in the same ballpark. You'd be best just driving gently and letting the car do the thinking. I gave P&G a pop and yes you can get good mpg's (when I got 91 mpg over 20 miles) but you'd die of boredom OR a roadrage attack lol.

I drove to Battersea the other year from Yorkshire. It was 80 (Car reading = 72 actual) down the motorways, 2 hours crawling into central London, park up, enjoy crap day out at EcoVelocity, spend 2 hours getting out of London and driving back up north at 80. I got 57 mpg that day without trying with heating and a/c on.

It has been mentioned before on here and other forums but I'll reiterate it (in a nice way without trying to sound like a forum bore). Just let the hybrid car sort itself out. It does a cracking job. Toyota have spent 14 years perfecting it. A mistake a lot of newbie owners (me included at the time) is to try and out smart the car to get better mpgs. Generally over the long term you won't. I know it's addictive to drive on electric and watch your mpg's read 100+mpg for a few miles but eventually the car has to top up the battery more than it would have and will use more fuel trying.

Just ask the older members on here who will agree - I think :)

Sorry for the late reply, but I just wanted to say that I agree with everything you said.

55mpg is mediocre, but it is over a full tank with a fair few rounds of bumper to bumper, 2mph average driving for 10s of minutes at a time. In those situations, I haven't yet found a way to avoid the HV Battery depleting. At first, it's great as everything is quiet, and the mpg even goes up 0.1-0.2mpg, but then the engine kicks in, makes a roar, and the mpg drops through the floor. Still better than the 12mpg I saw in similar situations with my last car (1.2 NA).

When I do concentrate, and the traffic is moving, I have practiced enough to get a pretty good glide, and on a less than a 10 mile route, I have seen about 70mpg. I'm sure that I could get a bit more, but agree that it's not a good idea to annoy every other driver, and so I tend to kick in the petrol engine at about 10mph on the acceleration, and not drop too far back from the car in front. Wayne Gerdes I am definitely not!

David

[kithmo]

Sounds like you have AC or heat on David and turn off the stereo if you're sat a while in traffic as well.

[orangezorki]

Sounds like you have AC or heat on David and turn off the stereo if you're sat a while in traffic as well.

Alas, no (mostly). I rarely use the AC and try to keep the heat off when I know the car is cold. As for the stereo, please don't go there. I can't bring myself to make actual threats of violence, much less have the intention of following them through, but oh the tutting you would get... Oh the tutting!

Mainly, I think it's a problem that is only seen in rush hour or immense traffic jams that are fortunately not seen out of the centre of a few cities. I am completely open to suggestion as how to eek the most out of the four bars I tend to have in a jam though.

David

[Joseph D]

Sounds like you have AC or heat on David and turn off the stereo if you're sat a while in traffic as well.

A lot of people seem to make comment about not using the A/C to save ?? mpg, which bemuses me. I will concede that it may make a measurable difference if you are in an either extremely cold (< 3℃) or extremely hot (>35℃) climate, but I honestly have to say that I can not conclusively prove that running the A/C on auto (set at between 21-24℃) makes a measurable difference per tank. I do, however, concede to not running the climate control (some mornings) for the first 5 or so mins until the engine has warmed a bit.

As for not using the stereo to improve consumption, that just make me LOL.

Considering that the difference of the same journey driven during the night vs during the day in similar conditions, with the major differences being OAT (say 12℃ at night vs 20℃ during the day) and light vs dark, even then the difference in fuel consumption is relatively small considering the extra energy demand. Just the headlights alone draw somewhere around 55W a piece, not to mention side lights and tail lights. Then there's the extra heating. Please hear me, I'm not saying it makes no difference, it does. What I'm saying is it doesn't make that much of a difference that you should suffer by being uncomfortable chasing the almighty MPG.

While I'm at it, part of the illusion is created by using MPG as a measure of consumption. While it has it's uses and is convenient in some circumstances, its exponential nature makes comparisons meaningless if phrased incorrectly, especially the higher the mpg's get (particularly above ~28 mpg). For example, the difference of 5 mpg between 20 - 25 mpg is huge, compared to the difference of 5 mpg between 65 - 70 mpg. If you looked at the inverse of the same figures, i. e. in gal/100 miles these same differences would be (remembering that lower is better this way around) 5 - 4 Gal/100 mi (1 Gal/100 mi diff) vs 1.54 - 1.43 (0.11 Gal/100 mi) respectively.

My above paragraph is off-topic and it is not my intention to draw this thread into a mpg vs gal/mile debate (happy to start a new thread, if that interests anyone), but merely to make the a statement such as "I lost 5 mpg doing xyz" is actually meaningless, because it matters what the the from and/or to mpg figure is. You need to say, "My mpg changed from 72 mpg to 67 mpg" to convey any meaning. In this example the difference of 5 mpg is only a difference of 0.10 gal/100 mi. However, using the inverse scale, gal/mile (or gal/100 mi which gives numbers that are larger and therefore easier to work with) it is perfectly acceptable to make the statement "I lost 0.1 gal/100 mi" as the scale is linear has the same meaning regardless of the from/to numbers. If you use Fuelly, for an easy way to see this effect graphically using your own data, change the display unit to L/100km (as this is the only option for a linear scale in Fuelly) and look at your consumption graph. While the numbers may not mean anything especially to you, you will see it is a lot less volatile looking and so conveys a more realistic picture of your economy efforts and more particularly the significance of any fuel saving efforts.

Wow, didn't really mean to go all the way there, but I hope some, at least, find this interesting. My main aim was to show that whether you are getting 55 mpg, 60 mpg or 70mpg, you are getting some really impressive fuel consumption figures, and any improvement beyond is reasonably insignificant compared to the improvement from 28 or 35 mpg that you were getting before.

[Grumpy Cabbie]

We all know the difference heating makes to hybrid economy - kills it.

And whilst the a/c on a Toyota hybrid system is VERY efficient and doesn't kill your economy like it would in a traditional car, it does still make a dent. All my high average mpg's - read over 75 mpg - have all been with a/c and heating switched off. With a/c on it does draw a weeny bit of power from the Battery (lots when it's first switched on on a very hot day and makes a heck of a racket in the process) and that does affect the top end mpg's.

However, for most people the trade off between comfort and getting 65 mpg instead of 75 mpg (or is it the other way around) is one most people are willing to take.

[joancy]

I have the exact same hybrid and year I was getting 49-50mpg now summer is here I am getting 54mpg the longer I am in the car the more I seem to get, if this increases I will post the results. Joancy