Power lost on slightest spin of tires

The traction control makes sense at speeds above 5 or 10 mph.

At a crawl, or from a stop, the wheels should give a little spin... not a full blown shred the tires spin, but a little something to work on getting going.

Staying stopped is obviously not the right answer since bob has the gas to the floor, let's put a little torque to the wheels and see if anything good happens.

If you're dead in the water, do you just wait till spring to move ahead out of the traffic light? Call a tow truck.. what happens next?

 

I agree some tests need doing. Getting stuck is part of winter and I've never seen a car that could always get up a hill including lots of 4 wheel drive vehicles.

Never had one myself, but I've sat at the bottom of some hills with ice on the road, right along with them, while everyone had to wait for a sand truck to arrive.

And stopping on a hill makes restarting again a problem with every car I have ever driven in winter. Backing down and re-trying works sometimes, other times I've had to turn around and find a different route. Prius is not that different from other cars.

Traction control I never had, so have nothing to compare with. But I have had a car with limited slip differential, and I'd take the Prius any day. Sure it gave me more traction, but it also tried to go off the road sideways all winter too!

 

How about not being able to get up a gravel driveway, with only a slight incline, in the middle of the summer? Slow speed, fast speed, any speed or accelerator pressure did no good at all. Traction control kicked in and that was the end of any forward movement. Finally wound up having to back up the driveway.

Folks, you can rationalize, test, say it doesn't happen to you, those it happens to must be bad drivers, sell the car, etc. but the problem exists and it is a serious one for those of us who have encountered it.

 

You've got the right idea, but you could still spin your tires too fast and damage the electric motor.... what we need is a "tire rpm limit" below a certain speed.

 

OK. Here's a link that gives a more definitive answer as to the benefits and downsides of traction control. This link concludes that it is not unheard of for people to get stuck in their driveway after even a light snow fall because of their car's traction control system. And so this is why many cars offer the ability to turn off traction control.

Basically if you are driving a car with traction control expect inconsistent results. Sometimes it will help you out of snow, sometimes it will just get you stuck in snow. Since it appears that it could damage the Prius transmission system to turn off traction control, it probably means that with the Prius unfortunately you may be trading of the ability to turn off traction control to gain the advantages of a really sophisticated transmission system.

Incidentally, the HIghlander and Lexus SUV hybrids that use the same basic system as the Prius get around this because they also have more than one electric motors powering different wheels. With the hybrid AWD systems you have the ability to increase electricity to the motor driving the wheel with the most traction. Possible solutions to making the Prius better in snow without changing the tires is:

1) Add separate electric motors to different wheels to make Prius an AWD Prius
2) Find a way of protecting the Prius from damage due to wheel spin and then offer a traction control defeat switch.

With that said it potentially makes traction control and VSC sound like lame and useless features that aren't worth the money. We'll traction control is mandatory to protect your Prius from damage. However, possibly the VSC may be questionable. However, I don't believe VSC kicks in for accelerations from a standing start. The VSC is more intended for if you are already moving and are about to make a turn on a slippery surface. So eliminating VSC is probably not going to change the situation of getting no power when the traction control system detects wheels slipping at any speed.


Here's the link:
http://www.powertrax.com/tractioninfo.html

 

Hi Popoff... it sounds like your case warrants merit.... I would guess if your tires would only turn barring them going over a certain rpm, you would be able to get up the hill correct?

And if you could get up the hill, what do you suggest as a permanent way to fix this problem?
A. a button to disengage traction control with a rpm limit in place?
B. leave traction control in place but limit the rpms?
C. Not use traction control at all?

The problem I see with turning off TC upon demand is that you may be caught by surprise and not have time to fiddle with or engage it when needed?.. It would be like trying to put a 4X4 into 4 wheel while sliding towards a ditch!... thats why they made all time 4X4?

All in all, I like the idea of traction control, but I also like the ideal of my tires turning when I press the gas if there is any traction.... maybe thats a contrast of terms?

The illustration about not being able to go up a gravel road unless the tires will spin verifies my illustration of how 1+1 =2 .
Maybe the traction control is too sensitive and kicks on too easy.... if there any traction at all, it shouldn't be kicking on!

They do limit the rpms by fixing it so the maximum speed of the car cannot go above 115 mph or so. Why can't this "rpm limit" stay in place but have an ability to turn off the traction control?

 

Here's another link that describes how traction control gets a Mustang Cobra to stall because it kicks in when accelerating hard on dry pavement. So the conclusion is traction control issues are not at all specific to the Prius, they are a just a fact of life of traction control.

http://www.epinions.com/content_211293474436

In fact I've heard that traction control, VSC and ABS can all be achieved and outperformed by a skilled professional driver. Really all the electronics is about trying to make "professional drivers" out of the average driver. So it's probably true that if you want the best possible traction you can get without getting AWD then you want a plain ordinary car with none of the above safety features and as long as you turn out to be a skilled professional driver you'll come out ahead.

 

I've even had simliar situation of my Jeep Grand Cheerekee...most of the time its wonderful, but I have gotten high-centered before in the snow and have had only the one tire spin that has no traction.... its quite frustrating when I am in 4 wheel drive and only one tire will spin?


I have been quite sure that if I could only get one of the other tires to spin I could have gotten free, but It wouldn't for some reason?

Its explained in the link driveprius left :

And here is the revelation as to why you can't drive up your gravel driveway:

 

The software in the car must control the amount of wheel spin and brake interaction for the wheels control.

They could limit wheel spin with the mechanical brakes on the spinning wheel first before doing the engine cut off.

They could also set the wheel spin detection to a slightly higher spin rate before doing anything.

Which brings up the possiblility that Toyota has already experimented with this code like they have with other aspects of the engine and hybrid control. So all our Prius may not be the same here at all. And maybe with some more complaints Toyota will update the settings for this.

It should not be that hard to limit wheel spin with a brake first, and then with engine only when torque was excessive or else both wheels started to spin.

 

My 2004 Prius with Yokohama Ice Guard winter tires does a far better job on snow and especially ice than most cars on regular "all season" tires. Especially on ice, I have to be careful braking when I have idiot 4x4 pickup and SUV drivers on my nice person.

A 4x4 does NOT stop faster on glare ice.

My parents have a 2003 Buick LeSabre and the old man insists on running 4 studded snow tires - Cooper WeatherMaster ST/2 - in winter. That car is a tank, but it can only plow through 1-2 inches more snow than my Prius before it grinds to a stop.

On glare ice, his Buick with the studded WeatherMaster tires has huge traction advantages over my Prius with the Ice Guard tires. I'd prefer studded tires.

I had a 1992 Honda Prelude that was far worse on snow/ice, even with winter tires. It had a high strung motor, so it was incredibly difficult to modulate the power. Either it would stall or the front wheels would be spinning like crazy. I refused to drive it in winter, even with studded Nokians.

I just got back into Winnipeg and now that it has warmed up to the freezing point, there is a lot of ice on the roads in the morning. I fear being beside an empty RWD pickup, van, or car at a red light: once the light turns green, they step to the side and fishtail all over the place.

Before I left when we had some heavy snows, I was stuck a couple of times at a left turn lane while waiting for some idiot Mustang or Camaro driver to get going. Those RWD cars are worthless on snow/ice and should be banned in winter. C'mon, 2-3 inches of snow and they're STUCK??

 

I wonder how studded tires would compare if on the prius?

I agree studded tires are way better than "any" ice tire on ice, but as traction increases, so the MPG drops.... but thats an ok price to pay for special circumstances.

 

I understand that you're upset about this, but this does not necessarily mean that there is something wrong with the traction control system on your Prius. As I said before, if you can determine that a similar car (size, weight, FWD, TC, etc.) manages the same terrain significantly better than your Prius then I think you have something to complain to Toyota about. But it may be that your driveway is not TC-friendly for some reason and you need an AWD car or one which you can disable TC on. Or to get your driveway resurfaced or get different tires.

BTW, TC is enabled on the Prius in reverse. It's just the weight distribution that's different.

 

Does anyone with a CAN-View live in a snowy area? Can Eifler access any TC, ABS or other data on the Can-View?
Can we dump CAN-VIEW data to a laptop when stuck on a hill?

I am defining the problem as two fold:
TC condition A- Power is stopped from going to either drive wheel.
TC condition B- TC prevents limited spin to get going from a dead stop.
If someone has better definitions please chime in.

I'm working on a gyro-accelerometer data logger to gather data for stability analysis at highway speeds. This might help with this problem.

 

This is my vet's driveway. I imagine many cars of all types and flavors go up this driveway on a regular basis under many different conditions

Would you suggest I go out and buy a new Prius and run a side by side trial with mine?

I've gotten tired of this discussion. Over and out!

P.S. there are numerous posts on this thread and in other threads upholding my position. TC is dangerous and needs a fix.

Over and out for the last time.

PPS: I understand TC stiil works in reverse and that the weight shifts. Why do you think I backed up the driveway to begin with? I'm on my way to get an inclinometer and run some tests. Maybe there indeed something wrong with the slightly pitched driveway that everyone else traverses with no problem.

This time I really mean it.

OVER AND OUT!

 

Something should be done about it before some accident happens.
Great discussion!

 

Dude,
I'm just trying to be helpful. Now that you mention it, finding another Prius to try on that terrain would be a very interesting test. Not suggesting you buy another one for that though. Maybe your Toyota shop would lend you one. It could be there is something amiss with your particular car. Good luck!

 

I grew tired of this discussion long ago and many threads ago. Yet I'll weigh in on it one more time. FWIW, I haven't read all 8 pages. The solutions are obvious but I don't know why I bother.

I'm not PC, I'm too old to start now and I'm not running for office. If you've never developed a skin, go no further. You were warned.

One thing that needs to be considered is that there are different levels of driving ability. Just because someone has driven for 50 years doesn't mean they are a good driver, especially when hopping into a vehicle with a HUGE amount of low end torque in difficult road conditions. That changes the driving equation considerably. One doesn't put Aunt Edna behind the wheel of a Formula 1 car and expect good results. Throw in ice and snow and it'd be a certain disaster. (it would be even for an F1 driver)

The Prius is such a vehicle, and it's a sleeper since it does it so quietly, not with the roar of a F1 car. The motor provides much higher levels of torque at low end than most ICE powered vehicles do. If the tires lose traction and TC kicks in it's because the driver is trying to feed too much power to the wheels for the road conditions. Period. There can be no other cause. Back off on the throttle, don't continue the mistake repeatedlyand expect a different outcome. Not to learn from it is _______. (fill in the blank, grade it wrong if you chose smart, intelligent or something similar)

There are a number of solutions, all require one to take responsibility for ones actions.
1. Increase the traction to the ground. Replace the tires with better rubber more suited to the conditions. Learning to put chains on the car in slippery conditions belongs here. In short, increase the traction, you choose the method. If you can't manage #2 this is an absolute must.

2. How does one tactfully tell someone to learn to handle the torque? Learn to drive? No, that isn't PC.

3. Park the car when the demands of driving exceed the drivers ability and equipment (see #1 & 2). You are responsible for driving safely.

4. Sell the car and buy an ICE powered car that doesn't have the large amounts of low end torque if one can't manage #1,2 &3.

5. Blame others and mention lawyers and lawsuits and how terrible the Prius is. What am I saying? That isn't the problem. Scratch #5.

If you won't do it for your own safety then do it for the innocent driver that you're about to take out with your "out of control" driving. Spinning tires is being out of control, TC just removes the spinning tires, the result is the same. It's a wonderful feeling to save the environment so that one can put others at risk by collision isn't it? Is the irony lost on me?

FWIW, we drive in Maine- there is no good driving. All year long we either drive on mud, loose gravel, or snow and ice. Heck, even my wife can drive this vehicle in crappy road conditions. I told her of this thread and she just rolled her eyes in disbelief of you'alls driving ability or lack thereof. Her driving ability just took a huge hit upward in my eyes based on what little I did read in this thread and by her own admission she can't drive on snow and ice.

 

Rant mode on!!!

Well, which one is it, OVER or OUT??? This symanticly self-contradictory phrase has been poluting the airways since the original Dragnet was number one on the Neilson ratings. In two-way radio usage:

OVER means that you are done talking and waiting for the reponse of the other party.

OUT means you are done talking and do NOT expect a response from the other party.

So which one is it??? Over? or Out?

Rant mode off!!!

Over!

 

Nice reply Brian... I do not yet drive the prius, I am still awaiting my 06, but I conclude after reading your response that either their particular vehicle is malfunctioning, otherwise all you said is pertenent.
It would be fun for them to
A. get another prius and try as recommended, or
B. Let someone else drive thier car that is used to the torque over the same areas.

I have read suggestions from some that say to floor the gas and then immediatly throttle it down to match the speed desired, others as yourself suggest to take it easy to let too much torque get in the picture....
I guess I'll just have to see for myself.

maybe they can take their car to the dealer and try to get someone to get in the car if they can replicate the problem. That may mean taking them home to check out thier gravel driveway?....

Its comforting to know that many do not have this problem.... I recognize there are many different driving conditions out there. I'll just have to take it out and play with it myself when I get mine...

I am comfortable driving on wet ice.... even without a 4X4.
You just have to learn and know your limitations and constantly know your road surface and don't go beyond those limits. But granted, I can go places other drivers can't go with 4X4. Just yesterday I went up to Mt. Hood following 4X4's with chains on... I was in my 4X4, but only in 2 wheel drive, no studs, no chains and did just fine.
I could have popped in in 4 Wheel, but never needed it.
Driver skill definately has a play in the equation.

 

Rant away sir. Obviously I was referring to toilet paper.

"tearing off toilet paper is a two-handed operation: one to hold the roll, pressing the paper just above the perforated line, and one to tear away the sheet(s). if the roll is hung tongue-in, it's that much harder to get a grip on the right section (especially with an undepleted roll). but with the tongue hanging over-and-out , the perforated line is always in the right place for a clean, effective tear-off.

I have no clue as to what you are ranting about.

I'll spare you my rant concerning the proper spelling of "pollution". But as to usage, I would say you are polluting this thread with your off topic rant.

I wish you all the best.