YIKES: Experienced unexplained acceleration, already had brakes reprogrammed

When you're coasting and not pressing on the gas, the car will induce regenerative drag. It sounds like the tires lost contact with the wet road and the regenerative drag got erased?

I'd be wary of any suggestions of unintended acceleration when it involves wet road. You should've asked here first before going to NHTSA.

 

Can you provide the coordinates or a Google link to the exact place this happened?

Left or right curve?

Pavement?

Thanks,
Bob Wilson

 

Did the vehicle speed actually change?

RPM of the engine can increase on its own. That's an operational aspect of the hybrid system. A purging event to cleanse emissions will do that. Feel & Sound are out of the ordinary, enough to catch the attentive off guard, but speed remains unchanged.
.

 

I have made a complaint to Toyota HQ GB already. But mine was slightly different from yours. This only happened 3 times after the brake software updates.
Basically as I press the pedal it reaches around 25-30mph and then it won't go faster anymore and this is with foot pressed all the way to the bottom and you will have a none accerleration for about 3-4 seconds and you wonder if your foot is actually on the gas or not. Just you are about to wonder the car will get a big boost surge forward like it is running out of control.

It is totally weird.

 

Have you noticed whether it does that in all modes (ECO, PWR, neither)? Sometimes in my expericence, in ECO there seems to be a point of resistance--corresponding to the vertical bar in the oval HSD--but nothing so pronounced as you describe, and not in the other modes. I always thought it was designed that way to increase FE. Again, though, sounds different than your experience, but I'd be curious if you've correlated it with mode. (Other than that, it sounds like my '85 Golf with a bad fuel injector relay ).
~T

 

This is all in Normal mode. I dont drive in Eco mode. Very seldom in Power mode if I am really pissed with another car.

But this car really does have improved me, it improved my road rage, I no longer now have road rage and very good for anger management.

 

Just a thought, as I have a 06 and not sure how the 10's are when it comes to this.
It sounds to me like you were going down a hill. In my Prius when the battery reaches its full charge while going down a hill, regen kicks out and the engine starts up and revs a bit, meanwhile the car is speeding up. The friction brakes are now what are slowing the car and, ofcourse, its a totally different feel.
I can have this happen in many different spots and quite often.
Just a thought, but maybe this is what you experienced?

 

That sounds pretty scary... but I keep thinking that maybe sudden acceleration could be related to the cruise control being accidentally triggered. In my 2005, the cruise control lever turns around with the steering wheel and is constantly hitting my legs. Do you think there's any chance that while turning you accidentally triggered the cruise control to accelerate? I don't really understand why the cruise lever is in such a place that it's so easy to bang into by accident... seems like it could be a safety hazard.

-Ken

 

en someone says, "both feet were not on a pedal" i become concerned. too many people drive with one foot on the gas and one foot on the brake. i was taught not to do this as it can lead to confusion.

 

Our dealer said there is a safety feature when you press both brake and gas together - the engine (ICE) will stop. I don't think anyone drives like that as someone said here, your instinct is not to drive with 2 feet.

We did an experiment going about 40 mph on a road with no other vehicles keeping pressure on the throttle as if it was in a run-away situation. Then we just "bumped" the shifter to "N", which is a quick left on the shifter knob and the CVT instantly disengaged. Of course the engine was racing a bit, but you can easily stop the car and then shut down the entire system. "If" a future throttle problem is ever discovered, this simple maneuver should save anyone from a run-away situation unless it happened in bumper-to-bumper traffic. Well, then prepare to smack into the next car, but I still say driving with 2 feet is more dangerous.

 

Here we go again.

My money is on the cruise control being engaged.

 

Where did OP go?

Can he say it wasn't cruise kicking in or loss of traction?

 

Yep, kind of suspicious... only 4 posts..

 

There are people who has a life and not hang around here all day.

 

Really?

 

The whole cruse control thing makes alot of sense....

 

Yikes..indeed ! But more that you posted this problem on this site..Some of the shills here will come out and call you another Sikes opportunist...or even a liar...or even worse, incapable of driving your car correctly...Many here claim since they are geniuses and owned multi Priuses and since this has NEVER happened to them, this cannot be at all possible.So watch out !

I thought that the recall (Software patch), was to fix this similar problem .

Hopefully some even keeled people here can give you some sound advice...But then again I don't think anyone has a 100% solution to whats going on.

Good Luck and be safe !

 

My psychic debugging skills tell me you were in EV mode. The car will try to stay in EV mode if you're in it, then, if you persist in trying to accelerate out of EV mode, will fire up the engine (turning off EV mode) and respond to the pedal input.

The only use for EV mode is to move the car a short distance and then turn off, for example unblocking someone in a car park, or for forcing the engine off when the car is trying to perform an idle check. My understanding is that the third-generation car no longer has this warm-up bug, however.

Most of the time EV mode is counterproductive - it produces great immediate fuel economy numbers, but it wastes energy in discharging and recharging the battery. If you're new to Prius ownership, let it manage the charge level and leave the EV button alone.

If you weren't in EV mode, it sounds like the car is having trouble starting the engine. Check the engine oil level and make sure it isn't overfilled (above the MAX mark on the dipstick) - dealers commonly overfill the oil and it's a common cause of failed/slow starts. Otherwise get the dealer to follow the troubleshooting path for engine start problems.

 

I do not know about EV mode. I've only managed to get it to work if I was being ridiculously careful and at very very low speeds. It seems mostly a waste of time and unlikely anybody would really be in it unless totally aware of that fact.