One Year In A Yaris Hybrid

[Alan_B]

I bought my Yaris Hybrid one year ago and I have driven over 10,000 miles so I thought I would report how well it has done in that time as it is hard to find concrete figures.

I bought the car from a Toyota dealer when it was 7 months old with only 1,600 miles on the clock. The story was that the original owner had not got on with it. The dealer threw-in a full tank of petrol and I filled it up again today on the anniversary of its purchase.

I have driven 10,582 miles, used 858.86 litres of petrol at a total cost of £1,102.05. This works out at a year-long average of 56.01 MPG or 12.32 miles per litre or 10.41p per mile.

In the first six months I did 5135 miles at an average 53.04 MPG so things have improved, either because MPG improved with age or because the first six months was winter.

I have filled it up 35 times over the year, much more frequently than I had to with my previous car because the tank capacity is only 30 litres (31 at a pinch). Once or twice I have managed over 400 miles between fill-ups but not usually.

I do a lot of short journeys of between 0.5 and 5 miles in mostly free-flowing traffic at 30/40 mph interspersed with some 50/60 mph sections of road. Each week I make a return journey of 10 miles each way and another of 20 miles each way, with over half on motorway. Holidays and weekends account for some longer trips. I have taken to driving my weekly motorway trips at 60 mph to boost the fuel economy. This, according to the car, is a lot better at 50 to 60 mph than it is at 70. But basically I do too many short journeys to get the best MPG of which any car is capable (unless maybe a plug-in hybrid would suit this driving pattern).

I am disappointed about quite how far my actual MPG falls below the published test MPG figures (its about 75%). This must mean that the car isn't nearly as 'green' as Toyota claims. However the fuel economy is still not that bad and its a pleasant and relaxing car to drive around the suburbs. It has had one service and there have been no problems at all so far.

[Grumpy Cabbie]

Yeah the official ratings are nonsense and only obtainable with extreme care. But that applies to any car.

I always recon on 3/4 of the official rating. But saying that, you're meant to get 83 mpg and you're getting less than I get out of my Prius. Hmmm. Check tyre pressures as even 1 psi below will affect the mpg's at top end. When changing tyres try and get A/A rated low rolling resistance ones. I put a set of A/A Bridgestones on mine recently and they allow the car to coast along much longer than usual.

One last thought, you're not trying to out smart the car by 'forcing' the car to stay in electric or using EV mode for the last half mile before you park up for the night etc? There are so many posts from new owners doing these things thinking they'll help the economy when the opposite is true. Counter intuitive but true. Might explain your low mpg's.

[Heidfirst]

http://www.dailymail.co.uk/news/article-2766915/Revealed-The-car-makers-tricks-boost-MPG-claims-leave-drivers-forking-400-year-petrol.html

It is the same in the US where their showroom sticker mileage is seldom achievable in the real world.

The tests need to be revised to better replicate real world usage.

[Ethanedwards]

I bought mine new in Sep 12. Its now on 37K so I do a lot of mileage. I'm really not that bothered about mpg. Its sufficient, like you say it's a comfy cruiser. Had three services about 9 months apart. Replaced two tyres and two of the original contis now in the front are at about 4mm. So theyll be gone in the new year. I bought the service plan up to 50k miles so cost? thats not an issue. I bought gap ins up to five years and thats when the warranty expires so Ill replace it then. Probably an Auris hybrid. In summary I'm pretty satisfied with my little yaris. .

[Alan_B]

Grumpy Cabby, most routes home are slightly downhill and subject to a 30 mph limit so the last half mile is predominantly in EV mode without any forcing. But if the car has charge in the Battery it will run on EV at 30 mph and if the Battery has little charge it will quickly charge itself when the petrol engine is running. I don't see how the timing of the charging and discharging affects the fuel economy. The management system never allows the Battery to be fully charged or fully discharged so you only seem to get about 60% of the nominal capacity. The range under battery power seems to be 1 to 1.5 miles; I believe the Yaris has a smaller battery than the Prius.

My tyre pressures have been good whenever I have checked so that would be for most of the last year for which I gave the figures. I'm probably due another check now the weather is getting colder.

[MEP's Yaris GS]

Although the MPG is nothing on what is claimed (under test conditions, which will not be representative of heavy urban use) I'm still impress with 56mpg from it. I'd have said you'd be pushing only about 40-45mpg (at a push) in a standard Petrol Yaris driven well in similar conditions, so its still done 10-15MPG better (20%+).

[Ethanedwards]

Yikes...never been thst low. 56 is drive it like you stole it mpg in the depths of winter!

[Grumpy Cabbie]

Grumpy Cabby, most routes home are slightly downhill and subject to a 30 mph limit so the last half mile is predominantly in EV mode without any forcing. But if the car has charge in the battery it will run on EV at 30 mph and if the battery has little charge it will quickly charge itself when the petrol engine is running. I don't see how the timing of the charging and discharging affects the fuel economy. The management system never allows the battery to be fully charged or fully discharged so you only seem to get about 60% of the nominal capacity. The range under battery power seems to be 1 to 1.5 miles; I believe the Yaris has a smaller battery than the Prius.

My tyre pressures have been good whenever I have checked so that would be for most of the last year for which I gave the figures. I'm probably due another check now the weather is getting colder.

It wasn't a personal dig. I'm just grumpy by nature.

If you let the car do what it wants (by just driving it gently) it'll get the best economy. The problem arises when people (often new owners) try and out smart the car, such as switching the car manually into EV mode, or being extra cautious on the accelerator to stop the engine running for the last mile home, thinking that as the car charges the Battery the next morning they'll run the Battery flat in the evening, getting a 'free' mile without petrol and hopefully helping their economy. Sounds logical. What they don't realise is that in the morning the car actually uses the Battery charge to propel the car exclusively, with the engine only running to warm up (think of a diesel electric locomotive - as a rough guide). The benefit of the car doing this is to maximise fuel economy on the cold start warm up cycle. If you leave the car to its own devices you'll get 50 mpg during warm up. If one tries to override it thinking one is outsmarting the car, the car doesn't have enough charge in it for the morning and one will only get 25 mpg during warm up. This has a big impact on average fuel economy and is why some owners get 65/75 mpg averages and others 50/55 mpg. (ps if you floor the car during this weird warm up stage it switches out of it and you end up getting 25 mpg).

Clear as mud I know, but having been on hybrid forums for 5 years here and in the US, a common theme for new hybrid owners achieving below average mpg's in 9/10 times is because they're trying to outsmart the car. Obviously you're not, but hopefully the above gives some small insight into the magic employed by the hybrid system.

[Alan_B]

Grumpy Cabby, most routes home are slightly downhill and subject to a 30 mph limit so the last half mile is predominantly in EV mode without any forcing. But if the car has charge in the battery it will run on EV at 30 mph and if the battery has little charge it will quickly charge itself when the petrol engine is running. I don't see how the timing of the charging and discharging affects the fuel economy. The management system never allows the battery to be fully charged or fully discharged so you only seem to get about 60% of the nominal capacity. The range under battery power seems to be 1 to 1.5 miles; I believe the Yaris has a smaller battery than the Prius.

My tyre pressures have been good whenever I have checked so that would be for most of the last year for which I gave the figures. I'm probably due another check now the weather is getting colder.

It wasn't a personal dig. I'm just grumpy by nature.

.....What they don't realise is that in the morning the car actually uses the Battery charge to propel the car exclusively, with the engine only running to warm up (think of a diesel electric locomotive - as a rough guide). The benefit of the car doing this is to maximise fuel economy on the cold start warm up cycle. If you leave the car to its own devices you'll get 50 mpg during warm up. ....

I realise it was not a personal remark, Grumpy Cabbie, and I cannot figure out how to remove your quote of me in this reply.

I've never spotted this warm-up mode so I'm not convinced this is a feature of the Yaris. But I can look out for it on the display; presumably the petrol engine is shown as only charging the Battery and not turning the axle/wheels? And the instantaneous mpg is unusually good?

What happens if you live at the bottom of a hill? The electric motor alone is not powerful enough to manage much of an incline so you won't get the warm-up phase you describe and must be doomed to lower mileage.

Ethanedwards, remember 56 mpg is for the entire year. I got 53 mpg during the first six months so must have been getting 59 mpg during the last six months to make the average 56. Lots of people post that they achieve this or that mpg but I haven't seen anyone else give actual mileage and fuel figures over a long time period.

[Grumpy Cabbie]

There is a list (somewhere) of the various warmup cycles of Toyota hybrids. They change slightly as and when new models are released but the basic 4 or 5 stages are there, and usually hidden in the background as it were.

The mode I was refering to is there if you are light on the accelerator. If you floor it (effectively go into the power band) it jumps the stage. Sometimes people have reported a slight hesitation when pulling quickly out of a junction when first started on a cold day. That's usually when the car jumps the stage. If you just take it easy then the car remains in that weird stage for longer.

Does modern living and/or circumstance necessitate us having to drive in a way we sometimes wouldn't like? Sure. Do some people live at the bottom of a steep hill (your example)? Sure. They would have to accelerate harder and thus the car would skip this warmup stage and their economy would suffer. There again, driving up a hill ruins any economy. I guess also that some people live right next to a busy junction where they have to floor it to pull out. They too would miss this warm up stage. For me it works (assuming there's nothing coming when I pull out of my cul de sac. I drive off on the flat with the instantaneous meter reading over 50 mpg right from cold on a cold morning. During this period the hybrid meter is continuously drawing power from the Battery and not putting any back in. It also indicates the engine is powering the car, though I understand this isn't necessarily true at all times.

Told you it gets complicated and there's more to it. This was just a small example of how doing one thing thinking you're doing the right thing actually has a knock on and detrimental affect.

But if ever the time to be super gentle on a car it's when it's warming up. Not just a hybrid. I'm not familiar with the Yaris HSD gauges, but if it has a power or red band, try and keep out of it when the engine is warming up first thing. Easier said that done on busy roads.

UPDATE: Have a look at this link, making particular note of Stage S1a. This link is aimed at the Prius but applies to all Toyota hybrids with the odd slight amendment here and there. It gives a better idea than my waffle.

http://priuschat.com/threads/gen3-warming-up-stages.76501/#axzz3FonGUdzU

• when the start coolant temperature is below 40C, the warming up starts and continues for approx 50 seconds after S0.
• you can not enable the EV-Drive Mode during this S1a.
• the ignition timing is very late, after the top dead center.
  therefore the engine does not have enough power to drive Prius or charge
  Battery.
• basically, Prius can not use the engine power when you drive. Prius is driven by Battery power and the battery is discharged.
• it is good idea to drive slowly or stand still warming up in this stage.

[PeteB]

... I'm not familiar with the Yaris HSD gauges,..

I put a picture of the original Yaris HSD guages here:

http://www.toyotaownersclub.com/forums/topic/161220-eco-power-gauge/?p=1346474

During the warm up stage it has been said the ICE is running but not driving the car - I don't think that's strictly true - if it's probably only adding 1 or 2 % to the torque going to the wheels, but due to the design of the power split device it must be contributing something, however small. But it is true to say that during this phase, unless something snaps the car out of it (like welly on the loud pedal) the work is almost entirely being done by the electric motor.

Basically, to minimise warm up time, the ICE is run very inefficiently from a motive power point of view (the variable valve timing is either heavily advanced or retarded [can never remember which], but it's a mode that generates a lot more heat).

To me, it feels like the ICE is temporarily divorced from the Hybrid system while it does its' warm up thing, and one of the many facets of Hybrid driving that still fascinates me after all these years/miles of Hybrid driving (12/300k).

[PeteB]

Be interested to hear how the Yaris Hybrid owners have found living with the car in terms of comfort, accommodation, storage space, equipment levels etc...

[Cyker]

So far the only car I've driven that has matched or exceeded the manufacture mpg claims in my wubbly Mk1 D4D Yaris, so it's not unusual to fall short of the claims. I would have thought you'd be getting into the 60's at least tho'!

That said, the short journeys thing is a killer; I know if I did nothing but short journeys in my Yaris the mpg would probably go down the tubes too! I had originally thought that HSDs would be less affected by short journeys since they can just use the Battery, but it seems what you save on the Battery on short journeys gets wiped out because the petrol engine has to start up eventually and doesn't get enough time warm up to operating temperature :(

One thing that might be worth experimenting with:

I find in my D4D that, esp. in winter, if I drive more aggressively (e.g. 3rd when I'd normally be in 4th or 5th), the engine warms up much faster and then I can back down again for the remainder of the journey, whereas if I drove normally the engine cold light would stay on for literally half of my commute with the expected drop in available power.

Obv. you have no control over the gearing in the HSD, but maybe you can force it by accelerating a bit harder etc. and I do wonder if expending extra fuel initially to get the engine warmed up faster and then going back to a more sedate driving style for the remainder of the journey would let the car be more efficient overall?

I don't know what the engine dynamics of the HSD are that well tho'; I find the D4D really wants to be as hot as it can to get maximum efficiency out of it, as well as to burn off any deposits that would otherwise build up in the engine and exhaust.

The HSDs don't generally run that hot, and while petrol engines tend to be less prone to deposits building up in them, they are just as vulnerable to heat energy being sapped by a cold engine block!

IMHO they ought to think about putting an engine with more pull in the HSDs; I think the low torque of the Atkinson units is holding them back (That 1.5L engine isn't any more powerful than the 1.0VVTi in the Aygo and far less than the 1.3!).

I'm a little surprised they haven't gone the other way and looked at a low-RPM high-torque setup engine as these will always be more efficient than an equivalent low-torque high-RPM engine!

If they made the 1.5L two-cylinders instead of 4 that would give it a decent torque boost (Although it might need a DMF!) and it's a fact that less cylinders = more efficient.

[Ten Ninety]

I do a lot of short journeys of between 0.5 and 5 miles in mostly free-flowing traffic at 30/40 mph interspersed with some 50/60 mph sections of road. Each week I make a return journey of 10 miles each way and another of 20 miles each way, with over half on motorway. Holidays and weekends account for some longer trips. I have taken to driving my weekly motorway trips at 60 mph to boost the fuel economy. This, according to the car, is a lot better at 50 to 60 mph than it is at 70. But basically I do too many short journeys to get the best MPG of which any car is capable (unless maybe a plug-in hybrid would suit this driving pattern).

I am disappointed about quite how far my actual MPG falls below the published test MPG figures (its about 75%). This must mean that the car isn't nearly as 'green' as Toyota claims. However the fuel economy is still not that bad and its a pleasant and relaxing car to drive around the suburbs. It has had one service and there have been no problems at all so far.

I can understand why you might be disappointed by how far away your figure is from the manufacturer figure but you have already given the reason why you aren't getting close - and will never get close - to the published figures, which is of course the number of short journeys you do. To me, your economy sounds about right given the circumstances. I have the dubious honour of having nearly matched the 70.6mpg published figure for the Prius over a 12 month period but if I was doing journeys that short I doubt I'd see much better that what you've done. There were many occasions in the winter where I would look at the journey average when sat at the traffic lights a couple of miles into my journey and see a figure well below 30mpg!

That said, it does seem to be yet another story of the Yaris HSD delivering economy that - as GC indicated earlier - appears no better than a Prius/Auris might do in the circumstances, despite having a published figure which is ~10mpg higher. It would be interesting to know if anyone, anywhere has got close to that 80+ figure over a long-term average.

[Alan_B]

I don't know whether the same is true for the Prius and Auris but the indicated mpg falls off a lot between 50-60 mph and 70 mph. Usually when I take a long (motorway) journey I want to get there so drive at around 70 mph and this means I don't get great mileage even when I'm not doing the short journeys. The best ever figure I have achieved is 270 miles on 19.73 litres (62.3 mpg). Of this about 170 miles was deliberately driving at 60 mph on motorway-like roads. So what really disappoints me is that although the indicators on the car show that I might be able to achieve 70 mpg by driving carefully, I have never come close to achieving this between fill-ups.

[Alan_B]

Once a week I visit a location that is not in a 30 mph zone. When I drive away I have always noticed that I get about a minute of anomalously good mileage when the gauge shows quite high revs in the 'eco' zone as I gently accelerate up to ~50 mph but the mpg shows as 75+. I think this must be a manifestation of a start-up mode (mentioned earlier) that I don't notice when restricted to 30 mph at almost very other time. If only I could drive in this mode the rest of the time! Or is the car just confused and I'm not really getting the high mpg at higher revs that it thinks I am?

[Grumpy Cabbie]

Once a week I visit a location that is not in a 30 mph zone. When I drive away I have always noticed that I get about a minute of anomalously good mileage when the gauge shows quite high revs in the 'eco' zone as I gently accelerate up to ~50 mph but the mpg shows as 75+. I think this must be a manifestation of a start-up mode (mentioned earlier) that I don't notice when restricted to 30 mph at almost very other time. If only I could drive in this mode the rest of the time! Or is the car just confused and I'm not really getting the high mpg at higher revs that it thinks I am?

You can drive like that at the rest of the time. That's how people are getting these seriously high tank averages.

It's being steady on the accelerator that does it. Drive at 50 mph on the flat and you'll find the mpg's will be over 80/90 mpg for the entire time. I get those figures out of my worn out Prius - still. So the Yaris should equal or better them.

[Alan_B]

No, you misunderstand me. During this ‘magic minute’ I can accelerate and the mpg still registers around 75.

On the Hybrid System Indicator (a type of rev counter) there are three sections, Chg, Eco & Pwr. The Eco section is divided into six segments. You cannot go past the third segment in Ev mode and (unless your car is very different to mine) you must keep the revs in the fourth segment to achieve top-rate mpg at moderate cruising speed (50-60 mph). But during the ‘magic minute’ as
the car is warming-up I can take the revs right up to the sixth segment and the Indicator still shows mpgs in the 70s. It might well be a false reading but how nice it would be to be able to do that all the time.

[Grumpy Cabbie]

Sounds like yours is similar to the Prius but your six segments are only two on ours (see below). So upto the dividing line between 3 & 4 is where your engine will kick in, whereas ours it's the middle segment (below ECO below).

So during warmup yes you can go all the way to the far end of segment 2 in the Prius, just before Power. I guess that's the equivalent of segment 6 to you. Effectively the range of EV mode when manually selected. The link below is the Prius version and during warmup you can drive right into green section 'Optimal Accel Here'. Go into the red PWR power zone and the car jumps out of that special stage.

Does that make more sense?

[Alan_B]

This is what you get in a Yaris; very different format:

[Cyker]

Well we did have a couple of people who were regularly getting 70-something in their Yaris HSD (Yolina or something?); It does seem if you live in a totally flat part of the UK and your commute is primarily A-road and slower motorway with town bits where you can get some serious regen braking done, you can get the better mpgs regularly. :)

OTOH, the people who live in hilly areas seem to average much lower, more in the 50's :(.

This isn't a good time of year for looking at mpg anyway; It tends to get worse as it gets colder!

[Cyker]

Well we did have a couple of people who were regularly getting 70-something in their Yaris HSD (Yolina or something?); It does seem if you live in a totally flat part of the UK and your commute is primarily A-road and slower motorway with town bits where you can get some serious regen braking done, you can get the better mpgs regularly. :)

OTOH, the people who live in hilly areas seem to average much lower, more in the 50's :(.

This isn't a good time of year for looking at mpg anyway; It tends to get worse as it gets colder!

[PeteB]

This is what you get in a Yaris; very different format:

HSI.jpg

Hi Alan

It's showing exactly the same information (and has nothing to do with revs, BTW - it's the amount of energy being taken from or put into the Hybrid system).

If you straightened it out and laid it alongside the Prius display, you'd get the same readings in any given situation.

What you're describing is the warm up stage where it's almost in EV mode but running the engine at the same time (with the timing heavily adjusted to be very inefficient at delivering torque, but warming up more quickly). Almost 100% of the motive power comes from the electric motor, even if the HV Battery is low (2 bars) and may even take it down to 1 bar briefly. The aim is to get the catalytic converters and the engine warmed enough to work efficiently as quickly as possible.

In your picture, the needle is in the 'neutral' position; no power is is being demanded or regenerated -

As you press the accelerator, the needle moves upwards, and expresses the amount of power requested - the Hybrid system may deliver that by running the engine, the electric motor or both, and the split can change many times a second.

If you press the accelerator harder after the needle has reached the top of the scale, you'll be getting much worse mpg.

As you slow down or brake (gently), the needle moves below that position, indicating the amount of regeneration.

Once it reaches the bottom of the gauge you're at maximum regeneration; pressing the brake pedal harder still will add disc brakes to the equation, wearing and heating the brake parts.

[MEP's Yaris GS]

This is what you get in a Yaris; very different format:

HSI.jpg

As PeteB has said its actually exactly the same, same number of segments, and will I suspect behave exactly the same.

[gigondas]

What they don't realise is that in the morning the car actually uses the battery charge to propel the car exclusively, with the engine only running to warm up (think of a diesel electric locomotive - as a rough guide). The benefit of the car doing this is to maximise fuel economy on the cold start warm up cycle. If you leave the car to its own devices you'll get 50 mpg during warm up. If one tries to override it thinking one is outsmarting the car, the car doesn't have enough charge in it for the morning and one will only get 25 mpg during warm up. This has a big impact on average fuel economy and is why some owners get 65/75 mpg averages and others 50/55 mpg. (ps if you floor the car during this weird warm up stage it switches out of it and you end up getting 25 mpg).

.

Very interesting, thanks for explaining the 'dark art'