Tests Raise Questions on "Runaway" Prius Claim

Posted: Mar 15, 2010 10:56 a.m.

Since repots surfaced about California driver James Sikes’ claim that his 2008 Toyota Prius had raced dangerously out of control, extensive testing has been done to get to the heart of the matter.

The results are in and they don’t look good… for Sikes.

Jalopnik published a leaked memo related to the investigations surrounding the incident: “According to the memo…prepared for members of the Oversight and Government Reform Committee of the U.S. House of Representatives, a thorough investigation of the Prius in question revealed that, while the brake pads on the car were worn down, technicians from both Toyota and NHTSA were unable to duplicate the unintended acceleration Sikes claims.”

It’s even being questioned whether Sikes attempted to stop his Prius at all.

“During and after the incident, Sikes said he was using heavy pressure on his brake pedal at high speeds,” says Fox News. “But the investigation of the vehicle, carried out jointly by safety officials from the National Highway Traffic Safety Administration and Toyota engineers, didn't find signs the brakes had been applied at full force at high speeds over a sustained period of time, the three people familiar with the investigation said.”

Instead, the Wall Street Journal reports “While the brakes were discolored and showed wear, the pattern of friction suggested the driver may have intermittently applied moderate pressure on the brakes...”

An independent test conducted by Edmunds on a similar Prius found no evidence that Sikes could not have stopped his car if it, in fact, did accelerate out of control.

“The plan was simple,” explains Edmunds. “We would hold the throttle wide open and see if we could overcome the raging engine (and electric motor) by simply applying the brakes. After that, we'd try slipping the shifter into neutral before applying the brakes. And because some people have expressed concerns that a panicky shift towards neutral might wind up in reverse instead, we would shift into reverse on purpose to see what would happen -- at speed with the throttle floored, just like the preceding cases.”

Edmunds’ Prius functioned as designed. Its brake override system kicked in, allowing for test drivers to safely bring the Prius to a halt. As for the claim that Sikes made about not wanting to shift into neutral in fear of flipping his car, Edmunds found no evidence of that happening either. And when they shifted into reverse, the car operated as if it were in neutral.

Of course, neither study is definitive proof that Sikes’ Prius didn’t malfunction like he says. They do, however, cast a whole lot of doubt on his claim.

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