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Prius Problems plus Toyota Sales Slump

hawk20

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Car giant Toyota has been hit by more than 100 complaints in the US and Japan about brake problems with its flagship Prius hybrid, it has emerged, in a new blow as it grapples with massive global recalls.
The Japanese company's sales have been battered in the US -- Toyota's biggest market -- after recalls of top-selling models to fix an accelerator pedal that can stick in the depressed position.
The new Prius petrol-electric hybrid, which went on sale in Japan and the US in May 2009, is not part of the recalls that extend to Europe and China, covering nearly 4.5 million vehicles.

http://news.aol.co.uk/toyota-hit-by-new-blow-over/article/201002022355032311523
 
Toyota are not having a good year, one way or another.

The acclerator pedal issue is a very good example of how reusing a sound design brings massive economies of scale while reusing a bad one leads to massive headaches. There are lots of interesting parallels in other markets (e.g. software).

I bet there's been some schadenfreude in the boardrooms of GM & Ford...
 
Peugeot are already working out how to call back all the Toyota based product in their line-up (107, Crosser, C1 etc)

By all accounts Toyota will be spending £1.5b on workshop time alone...
 
Pruis = Silly car
 
Pruis = Silly car

Yup. Given that all the power comes from the petrol engine, it would surely be more fuel-efficient if you stripped the batteries and electric motors out (because it would then be much lighter) ?!
 
Yes, the Prius is a (sort of) triumph of marketing over substance.

I never really understood it until I went to the States and saw a few driving around. Prior to that event, I couldn't understand why the hell they put a petrol motor in it. Why not a small diesel? It would then make far more sense, and it would then properly be an eco-alternative. But petrol? It undoes all the otherwise good work.

Then I went to the States, and I understood in an instant. Diesel, to an American, is a fuel fit only for trucks. An eco-conscious housewife is not going to want to get her hands covered in fuel oil. The Hollywood eco-luvvies can't arrive at an eco-fundraiser stinking of diesel, can they?

So the Prius got petrol, and all the eco work was for nought.

Fact - my S211 E320CDI returns better mpg than a Prius would doing the same work.

Fact - my brother (who lives in the USA) has a Prius. It is s***.
 
Like I said, unless I'm missing something fundamental here the Prius is a hugely flawed concept.

How can using a petrol engine to charge batteries that drive electric motors be more efficient than losing the (significant) weight of all the electrics and using the petrol engine to drive the wheels directly?

Even ignoring the (big) weight saving, in a hybrid you have two sets of losses involved in battery charging and electric drive motor(s). A mechanical gearbox between petrol engine and wheels would surely be more efficient, unless you have a LOT of regenerative braking involved.
 
Like I said, unless I'm missing something fundamental here the Prius is a hugely flawed concept.

How can using a petrol engine to charge batteries that drive electric motors be more efficient than losing the (significant) weight of all the electrics and using the petrol engine to drive the wheels directly?

Even ignoring the (big) weight saving, in a hybrid you have two sets of losses involved in battery charging and electric drive motor(s). A mechanical gearbox between petrol engine and wheels would surely be more efficient, unless you have a LOT of regenerative braking involved.

Look at the vauxhall ampera/chevy volt.

This type of hybrid works as the petrol engine is used as a generator to charge the batteries. The car is electric drive. Why is this more efficient?

1.Less transmission losses
2. Engine runs as constant RPM so less fuel actually used as its acting as a generator.
3. Once the batteries charge up, the engine switches off, this doesnt occur that often in a prius, but the volt does so much better.

For a petrol car of the prius's size the MPG is unriviled. However with a diesel this would have been a lot better still, but Japan and the US turn their noses up at diesel, as they percieve wrongly that its particulate emissions are bad for the environment, when they are not as the are larger PM10's, not the more dangerous PM2.5's you get from a petrol engine.

I dont buy into the carbon dioxide, climate thing either, and cars like the prius are a fad, not because they use it a bit less fuel, but because they a crap cars sold on the belief you are doing something good for the world, when in fact you are doing nothing but lumbering yourself with a bad car.
 
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I may be way off here but I think the sums are roughly.

Internal combustion engines are only 20-30% efficient in converting chemical energy in to mechanical energy. 0% efficient when waiting at the traffic lights.

Electric motors are 80% efficient. So charging batteries with an ICE is not ideal, but at least you do not waste energy when stationary or slowing down.

So why hybrid? Despite most journeys being short people still want the capability of driving longer distances, so an in ICE is needed.

I’m sure there is a future for electric vehicles and the Prius is a necessary first step, but it’s time to quickly move on..
 
Whilst I positively hate rushing to the Prius' defence, I think you are missing a bit there, Bill!

The batteries are not charged directly by the petrol engine. They are charged, as I understand it, by the regenerative effects of braking and over-run. The motors act as generators when in these situations.
 
Its such a shame that virtually all car companies are opting for the quick and easy solution of electric cars rather than continue developing Hydrogen fuel cells. BMW recently pulled out - MB still working on them.

There is absolutely nothing 'green' about using batteries, the amount of harmful chemicals which must be mined, then transported across the world only to knock a small about of CO2 off the exaust gases.
 
I wonder what is the life span of these batteries? and the replacement cost? a lot I guess.
 
Toyota's warranty on the electrical drive chain (batteries, motors, chargers etc.) is 8 years/100,000 miles. Battery replacement cost is around £3,000.

The cells are NiMH, and they are kept charged between 40% and 60% of their capacity. By not fully charging them Toyota reckon to maximise their life.

It is said that no battery packs have failed, the only replacements sold have been for cars involved in accidents.

Someone in the US worked out that 'gas' would need to cost $9.50 a gallon for him to break even on a Pious.
 
The Prius starts to make financial sense if you are company car driver travelling regularly into the CC zone and spending time in slow moving traffic.

I drove one a couple of years ago and it was quite cool at low speeds when the engine wasn't running. Sounded like a milk float.

The emmissions are so low it's got free road tax.

It's free for the CC zone.

And because company car tax is based on C02, and it's petrol (diesel has a 3% surcharge), its in the lowest band.

Thing is, it's expensive to buy and not very nice.

HD
 
Peugeot are already working out how to call back all the Toyota based product in their line-up (107, Crosser, C1 etc)

The Citroen C1 & Peugeot 107 are Toyota Aygo clones. The Citroen C-Crosser and Peugeot 4007 are Mitsubishi Outlander clones and not affected by the Toyota problems.
 
I have a mate who works at Toyota HQ in Epsom, and apparently Lexus sales are poor at the moment. No diesels (to speak of) and because sales are so low the dealers all want to jump ship -they are having difficulty persuading them to stay!
 
The batteries are not charged directly by the petrol engine. They are charged, as I understand it, by the regenerative effects of braking and over-run. The motors act as generators when in these situations.

And that is where some of the problems begin:

"In the case of the Prius brakes, it appears that the transition from regenerative braking to hydraulic braking is not transparent to drivers. Under certain conditions, the driver needs to press harder on the brake pedal to obtain the same stopping performance the regenerative system working in conjunction with the hydraulic brakes initially provides. Drivers are clearly upset by longer than expected stopping distances.

“What I, and others have been experiencing, is certainly not “runaway acceleration” or anything to do with pressing the gas pedal,” Robert Becker, an unhappy owner of a 2010 Prius, told TDB.


“But rather the loss of braking power or braking momentum when hitting a pothole, manhole cover, or the like. This requires the driver to press down again harder on the brakes to slow or stop the car,” Becker says.

Becker’s complaint is typical of others that ODI is tracking from owner communications on its Auto Safety Hotline. However, the existence of complaints does not mean the government will ultimately pursue the matter. The next step would be to open up an engineering investigation, one that has not been taken thus far.

Here is another Prius driver filing: “There have been several incidents in which my car seemed to surge forward while I was in the process of braking and hit a bump, railroad tracks or pothole. Initially, I convinced myself I must have been letting up on the brake when I hit the bump, but when this same thing happened three days ago on slippery, icy roads, I knew for 100% certain I had not let up on the brake. My car surged as I was slowly pulling up to a stop sign and gently braking. I came very close to hitting the car in front of me, had to push down on the brakes very hard, which activated the abs.”

I think what is going on is a combination of design/calibration choices and the compounding effects, forgive the pun, of the low rolling resistance tires, suspension settings and perhaps vehicle weight."



"....an internal NHTSA memo says: “It appears that when you hit a bump, the regenerative braking (front wheels only) cuts out, and there is a short delay until the friction braking kicks in. This results in loss of braking, which is experienced as acceleration (due to sudden end of deceleration from braking). Net impact is still a loss of braking/ increase in stopping distance."

NHTSA Tracking Braking Loss on Prius Hybrids | TheDetroitBureau.com
 
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My peer at work has a prius hybrid as a company car, and initially his comments were similar to those in this thread but he pays f*ck all tax per year and he also gets over 60mpg in ANY condition.

I think he comes off as a winner.
 

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