Acceleration Problem On Our 2010 Prius Gen V

The acceleration problem while going over the smallest bumps is exactly the same problem we are having on our new prius -- and we already feel that we are getting a very polite -- but utterly useless response from toyota 'customer satisfaction headquarters!

To the engineer -- see the forest for the trees -- it's dangerous -- over-correcting for a problem that isn't there!

We have left the car at the dealership -- and are fighting the good fight to get toyota to acknowledge the problem -- but we already feel we're running out of options other than an attorney.

Plus we are having to rent a car because my wife does not feel safe driving her 3 month old "new car" -- "the future of automobiles" are salesman called it!

Lets hope not!

 

I just made a complaint to NHTSA about my 2010 Toyota Prius cutting brake/sudden acceleration problem through its website at [email protected]. I recommend everyone do the same. This may be a safety issue. It does not appear like anybody doubts there is something troubling going on. It is all fine and good to discuss this issue here, but we all must remember to make formal complaints to the NHTSA.

 

I have no doubt that Toyota will someday come up with a patch for this issue.
What scares me is that it will most likely be a detriment to the car's operation or the driving experience in some unforseen way.

 

Exactly. Something like reducing regenerative braking simply to correct an occasional disconcerting sensation.

Tom

 

I think that is usually called reducing something to the lowest common denominator. A deadly habit of large corporations but cheaper than Congressional hearings and class action lawsuits or even just continued media interest. Remember Consumer Reports and the Audi? Did they EVER replicate that sudden acceleration? Ruined the resale on one of the best cars I ever owned.

 

I've been trying to convince myself that what I'm experiencing isn't acceleration, but rather something to do with the braking. However, it sure feels like a surge as I go over the same pothole several times a week. One of these days I'm going to ask someone to come in the car with me when it happens, and see what they think. Meanwhile, I'm getting increasingly concerned that there's a real problem and it's being ignored because someone thinks there's another explanation.

 

Yes, I am experiencing the same thing almost every day in my 2010 Toyota Prius IV!

Whenever I hit a pothole or a bump in the road while I'm braking, my Prius ACCELERATES INSTEAD!

This is PARTICULARLY DANGEROUS when I'm approaching a red light, because this problem has almost caused me to HIT THE CAR THAT IS STOPPED AHEAD OF ME!

I'm sending a complaint to the Department of Transportation and Toyota Customer Service... this is a dangerous safety issue that absolutely needs to be fixed, but Toyota is ignoring.

The 2010 Toyota Prius needs to be recalled along with all the other (earlier model) Priuses that were recalled.

 

I can guarantee that it is not acceleration. This is a perception issue that relates back to how we humans sense gravity. We are very sensitive to change, but not sensitive to steady state.

When you apply the brakes, the car begins to decelerate (negative acceleration). This creates a perceived force pulling you forward. As an experienced driver, you expect this force and it feels very natural. The braking force fits your internal model of how braking should feel. The braking force is uniform; in other words, it becomes the steady state.

Now we suddenly lose braking force, which means the car continues forward at exactly the same speed - acceleration is now zero. The loss of negative acceleration removes the perceived braking force pulling you forward. Since you were accustomed to this force, losing it feels like a push from behind. It isn't, but it feels that way since the braking force is now gone. This feeling of being pushed forward is exactly the same as the feeling of acceleration. That's why you feel like you have accelerated.

A really good example of how this works occurs in pilot training. When flying on instruments, the instructor will have the student put his head between his legs so that he can't see any of the instruments. The instructor then puts the airplane in a tight turn. After about 30 seconds of this, the instructor flattens out the turn into a gentle turn, but still turning in the same direction, and then asks "which way are we turning?" The answer is always wrong. To the student, the gentle turn feels exactly like a turn in the opposite direction. This is because the student has become accustomed to the hard turn and that became the steady state. Reducing the turn felt exactly like turning the other way. It is very disorienting.

Another example is trying to walk after spinning. Put your head on the end of a baseball bat, run around it in a circle for about ten times, and then try to run in a straight direction. You will run like a drunk. Your equilibrium becomes accustomed to the spinning. When the spinning stops, you perceive forces in the opposite direction, which completely screws up your ability to balance.

Tom

 

I highly doubt that complaining to the webmaster is going to do any good about an automobile safety issue. Let's try to find the real way to complain to the people in charge of automobile safety in America. Does anybody know how to do this?

 

Tom, sorry but this is not a perception problem.

Although your explanation sounds very scientific, I have been driving dozens of vehicles for 4 decades on these very same streets with the very same potholes, and I have never had the sudden acceleration problem with ANY vehicle I have ever driven until the 2010 Prius.

The 2010 Prius should be included in this recall.

 

Here's a form where you can complain to the U.S. Department of Transportation: Ask a Librarian

 

I think Kenc above says it most appropriately that we must let the National Highway Transportation and Safety Administration become aware of what Prius owers are experiencing (NHTSA) [email protected]. Yeah, maybe it is something that is supposed to be considered normal, but then again, what if it isn't and an accident occurs where someone gets hurt or dies, as was the case with the Toyota recall of the other vehicles with the accelerator problem. NHTSA will not know how broad this issue/problem is with our Prius if we don't let them know about it. I plan I sending in my concerns now.

 

NHTSA.webmaster is not the correct address. Use the form on the NHTSA website.

That you have not experienced the phenomenon in other cars does not mean there is automatically a problem. Have you driven a Gen2 Prius? Have you driven other hybrids?

If there were a problem with the braking (I'm not saying there isn't), it would be a completely separate issue from the two existing recalls.

 

Totally agree that the DOT and NHTSA both need to know about this problem.

Here are some tips on sending in complaints about this issue:

1. Use this link as evidence of the many discussions taking place about this issue on the 2010 Prius: Online resource for the Toyota Prius offering discussion forums, research, and shopping. - Search Results for 2010 sudden acceleration

2. Then, send your complaints to the NHTSA here:
https://www-odi.nhtsa.dot.gov/ivoq/Complaint.cfm

3. And send your complaints to the USDOT here:
Ask a Librarian

 

I'm sorry. Tom is correct it is a perception problem. Your previous cars had simple braking systems that just ignored a loss of traction. Your Prius has regenerative braking which is sensitive to traction issues and tends to react by stopping the regeneration for a very short time (Toyota has concerns about a rapid change in torque under these circumstances that could damage the HSD). The loss of deceleration feels like an acceleration and can be disconcerting, but is not a serious safety issue.

I find that the parallel issue, a loss of acceleration when one wheel loses traction, is a real safety issue as the hesitation can cause you to not complete a turn in time (oncoming traffic gets there first). I am very careful when merging because of this issue.

JeffD

 

The correct place to file a complaint is:

https://www-odi.nhtsa.dot.gov/ivoq/Complaint.cfm

And though I did post it in the other thread, here's the rebuttal to people who seem to be such fanboys of the Prius that they can't even acknowledge when something is broken:

http://toronto.ctv.ca/servlet/an/lo...us_brakes_100203/20100203/?hub=TorontoNewHome

 

Wonderful! Thanks so much for the links and the additional information!

 

Wonderful breaking news from CNN:

"Government investigating 2010 Toyota Prius brake problems, the National Highway Traffic Safety Administration says"

More bad news for Toyota: Feds probing Prius brakes - Feb. 4, 2010

And this came after ONLY 124 complaints to the NHTSA, one of which was my mine.

So it is VERY IMPORTANT that you make your voice heard, because it DOES makes a difference! File your complaints about the braking system in your 2010 Toyota Prius here: https://www-odi.nhtsa.dot.gov/ivoq/Complaint.cfm

They will take your VIN number so they can contact you if any progress happens on the situation.

 

This is the link to use (and please do it):
Office of Defects Investigation (ODI), File A Safety Complaint

 

Okay....I gotta put my 2 cents in again, for whatever it is worth. Yes, I had the brake issue with my 2010 Prius. When I took my car in last week to have this recall problem fixed, I had not had the issue of the braking problem happen for the previous several weeks. Why??? I don't know...only know it had seemed to have disappeared. Now that I have had this problem (I think it was to be a programming change), I still continue to have no problems with my 2010 Prius. The car is working just as I had hoped it would....hence the reason I purchased said vehicle. There comes a point that maybe we all need to back down/off of Toyota, and just say next time be honest upfront! They still make good vehicles. They just made some bad judgment calls in dealing with problems. We've all been there.