lincomatic
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Joined: Fri Jun 10, 2011 10:01 am
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Leaf Number: 3819

Stuck Throttle?

I don't want to get people too alarmed, because I wasn't in the car to observe what happened, but my wife had a big scare today. She was accelerating onto the freeway and then had to suddenly slow down due to stopped traffic. She hit the brake, slowed to a crawl, and when she released the pressure on the brake pedal, the car accelerated like the throttle was being depressed. She hit the brake again, slowed almost to a stop, and when she let up, it again lurched forwards. Finally, she pressed the brake pedal very hard. This time, the ABS kicked in, and as it was stopping, the front of the car dived... this really sounds like braking under power. The car was back to normal after she stopped and let off the brake this time. She insists that she didn't accidentally hit the accelerator, nor was there anything jamming the pedal.

Has anyone else experienced this? I'm wondering if I should take it in to the dealer or just chalk it up as a fluke.
Last edited by lincomatic on Fri Sep 23, 2011 12:04 pm, edited 1 time in total.
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Boomer23
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Re: Stuck Throttle

I'd be at the dealer's first thing tomorrow if that happened to my wife. Or she'd know the reason why!!! :shock:
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GeekEV
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Re: Stuck Throttle

Wow, that's weird. It sure couldn't hurt to have the dealer pull some diagnostics off the computer. I would imagine the sooner the better so the don't get overwritten or erased! I've sure never had that happen. The worst that happens to me is occasional inexplicably grabby brakes at low speed - there was another thread about that somewhere...

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lincomatic
Posts: 316
Joined: Fri Jun 10, 2011 10:01 am
Delivery Date: 06 Apr 2011
Leaf Number: 3819

Re: Stuck Throttle

Boomer23 wrote:I'd be at the dealer's first thing tomorrow if that happened to my wife. Or she'd know the reason why!!! :shock:
You're right. After posting last night, I decided to have her leave the car with me today. Hopefully, the dealer can fit in some time to try running some diagnostics, but I really wonder how they're going to figure anything out.

It was actually pretty surprising how calm my wife's reaction was about the incident. She said it was scary ... almost slammed into the car in front of her. Yet, she went on and drove it to a meeting before coming home, and had originally planned to take it to work again today.
lincomatic
Posts: 316
Joined: Fri Jun 10, 2011 10:01 am
Delivery Date: 06 Apr 2011
Leaf Number: 3819

Re: Stuck Throttle?

OK, I took it to the dealer this morning. As I expected, it didn't throw any fault codes. After it came up clean on the diagnostics, they drove the car on the freeway testing it, enough to burn off 2 bars of charge, and weren't able to reproduce the problem. They also called Nissan, and the reply was that they hadn't received an reports of similar incidents. Someone from Nissan is supposed to call me and follow up.

I know the knee jerk diagnosis is that somehow my wife had her foot on both the accelerator and the brake, but she adamantly rules out that possibility. I looked at the car, and there's no way the floor mat could have gotten caught on the pedal. Also, the relative positions of the brake & accelerator pedals is such that it's not easy to depress them together unintenionally.

I *hope* it was just a fluke that won't happen again. We love our Leaf, and I'm not trying to be a rabble rouser about the car. In any case, I've instructed her to shift to reverse (which causes the car to beep and go into Neutral when it's in motion) if the car ever accelerates uncontrollably again ... AFAIK, this is the fastest way to get the car to instantly cut the power to the wheels while leaving all the other systems powered up. If someone has a better way to stop unintended acceleration let me know. Trying to shift to Neutral is no good, because you have to hold the shift lever in Neutral for several precious seconds before it switches to Neutral. I once tried hitting the power button while the car was moving slowly, and that wasn't a good idea, because the car suddenly stopped an engaged the parking pawl even though it was still in motion.
palmermd
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Leaf Number: 1100011011
Location: Hermosa Beach, CA

Re: Stuck Throttle?

I suspect this was an ABS problem. Pure speculation on my part, but there are other reports here on the forum if you search regarding ABS behaving oddly when in an emergency situation and going on and off brakes.

I suspect what she thought was acceleration was actually coasting. If you have ever driven an electric car that had zero regen it is a strange feeling. The first time you let off the accelerator, you feel as if you are accelerating because you are so accustomed to a car decelerating when off accelerator. You quickly get used to it, but the Leaf has regen off throttle and if it ever did not you might think it was accelerating. If she hit the brakes and then let off and the car gave no regen nor power it might feel like it was accelerating.

I'm glad everyone was ok. I hope this is the last we have to hear about unintended acceleration.
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DarkStar
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Re: Stuck Throttle?

palmermd wrote:I suspect what she thought was acceleration was actually coasting.
This is my first thought as well. Lifting off the accelerator from an almost full battery in the EV has a completely different feel from an ICE.
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Herm
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Re: Stuck Throttle?

Step on the brakes with both feet if you have to, and hold the power button down until it shuts off.. and so be it if the parking pawl engages with the car still in motion, better than a crash.
smkettner
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Re: Stuck Throttle?

Since she actually stopped the car, I believe the story.
The rest that have runaway acceleration and cannot stop are total BS.

Keep us posted. It could have been a perception of speed issue.

BTW she does not drive with two feet does she?
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EVDRIVER
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Re: Stuck Throttle?

I seriously doubt the car computer made it accelerate on it's own. Likely a perception issue.

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