"I'm putting my foot on the brake and it doesn't stop."
More than 120 similar complaints have reached federal auto safety officials in Washington, D.C., and now it's clear that a large number of complaints have reached Toyota officials in Japan, as well.
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Mour says she had had her 2010 Prius just a couple of weeks when she tried to slow down because of backed up traffic and got a real scare, instead.
"Not only did it not slow down, it jumped forward," said Mour.
Mour said it happened on a rough road surface, which is consistent with Toyota's theory that the problem is an anti-lock braking system that disables the brakes for as long as a full second. That's far more than older models that have just a micro-second delay.
The way Mour describes it, "I jumped forward, I braked again, and I jumped forward again. Fortunately, I left enough room in front of the car so that I didn't hit anybody."
Mour became the 124th Prius owner to contact federal safety officials to file a complaint.. So far, officials say there have been four accidents involved in the complaints, and no fatalities. Mour also contacted Toyota corporate officials.
"They asked a lot of questions, which made me think I'm not the first person who's called them," said Mour.
Toyota officials in Japan said last month they revised the software for new Prius models being built, but they don't yet have a plan for some 270,000 2010 hybrids already on the road.
Mour says she finds that disquieting.
"In the meantime I have a car that I don't know if when I put my foot on the brake if it's going to stop or not."
The brake investigation has now also spread to hybrids of Toyota's premium Lexus brand, and Ford says its had some braking issues with its hybrid sedans, as well. Ford says it has made a software fix to solve the problem.
The braking issue couldn't come at a worse time for Toyota, which has begun installing a mechanical part aimed at solving a potential runaway acceleration problem on millions of other recently recalled models.
And also on Thursday, a Los Angeles man blamed Toyota for an accident that killed his wife. The family has now filed suit, claiming that Toyota should have addressed the issue years ago.