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Let's recap.
After 18 months, recalls totaling 9 million Toyota, Lexus, and Pontiac models, and investigations by Toyota, Congress, NASA, and the U.S. Department of Transportation's National Highway Traffic Safety Administration (NHTSA) unit ... what have we learned?
(1) A few accelerator pedals did stick open, for one of two very different reasons.
First, some dealers or owners fitted unapproved floor mats that were too thick, which could prevent the accelerator from returning to its usual position.
In the case of the horrifying and highly publicized crash of a Lexus that sped along a California freeway before overturning, burning, and killing all four occupants, a trapped accelerator pedal is thought to have been compounded by the driver not knowing how to turn off the engine in a car with a push-button start.

Loose all-weather floor mat jams accelerator pedal. Photo: NHTSA
(The answer: Hold down the "Start" button for a full 3 seconds. Hardly obvious without reading the owner's manual, which few people do for their own car, let alone the dealership loaner that crashed.)
Solution: Toyota amputated the bottoms of low-hanging pedals in some models, leaving clearance for even the thickest floor mats to be used without interfering with reshaped, shorter pedals.
Second, some other accelerator pedal mechanisms stuck under specific temperature and humidity conditions, remaining at about 15 percent of full throttle because moisture prevented a smooth return action.

2004 Toyota Prius accelerator pedal after being shortened as part of sudden-acceleration recall
Enlarge PhotoIt got complicated: Only pedal assemblies made by CTS, one of two parts suppliers, suffered from the issue. So Toyota [NYSE:TM] first had to sort out which cars got parts from which supplier.
Solution: Starting in February 2010, Toyota installed a steel reinforcement bar on models using pedals supplied by CTS (a different set of cars from those on the amputation list). The bar kept the mechanism away from the position where it could stick.
(For more information, see our summary, Toyota And Lexus Recall: Everything You Need To Know, which gives details on the two separate recalls to address accelerator issues.)
(2) Investigators found no "electronic gremlins" in Toyota's vehicle or engine control software.
This was the big fear, raised repeatedly by plaintiff lawyers and on the floor of Congress. Math is hard, software is confusing, and computerized cars are scary. The lack of technical knowledge among elected officials didn't help either.
But investigators could not replicate a single so-called "sudden acceleration" event once floor-mat and sticky-pedal causes were eliminated.
They pored through hundreds of thousands of lines of code seeking anomalies, unaddressed use cases, or any other problem that might make a car careen suddenly forward.
They even subjected Toyotas to high levels of electromagnetic interference, to see if systems weren't properly shielded. Nothing changed.
The full NHTSA report wasn't released by the DoT until this Tuesday, but as early as last August, the agency sent signals it had concluded that no electronic faults existed.
(3) Drivers who swear their car accelerated out of control are often wrong.
You put your foot on the brake, but instead of slowing, your car accelerates. The harder you brake, the faster it speeds up. Must be "sudden acceleration," right?
Well, no.
Have an opinion?
I guess that the electronic systems have come of age; this is good to know when your whole car is just electronics as is the case in an EV.
Unfortunately, the Prius shifter is a little strange. You have to hold the shifter in the neutral position for something like 0.5 seconds. Just flicking it into neutral for a moment is not good enough.
Perhaps every Prius owner should try this just to become familiar with this process.
Al Posted: 2/10/2011 4:14pm PST
There IS a problem here. I know from personal experience.
However, on the Prius, the ABS can be a little strange when braking firmly and going over a bump at the same time. For a 1/4 of a second the brake stops working. I guess this is normal for ABS, but it scares me when it happens.
DaveT Posted: 2/11/2011 11:41am PST
DaveT Posted: 2/11/2011 11:49am PST
My wife drives the exact same car so I investigated this incident in depth..reading the NHTSA report.. trying actions out on my wife's car to train her/us.
Yes, the start/stop button takes an amount of time that would definitely seem long and would be a major distraction if a driver has a 280HP engine revving out of control taking you to harrowing speeds.. but everyone should simply be trained to SHIFT INTO NEUTRAL if you don't know what else to do.
David Posted: 2/24/2011 12:20pm PST
FRANKOK Posted: 3/1/2011 4:55pm PST
Get off it and back to more likely cause NASA couldn't find - they reported:
"Our detailed study can't say it's impossible...." "Due to system complexity ... and the many possible electronic software and hardware systems interactions, it is not realistic to prove that the ETCSi cannot cause UAs.... Therefore, absence of proof that the ETCSi caused a UA does not vindicate the system."
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