(Runaway Toyota Prius story updated with statement from Toyota.)

NEW YORK ( TheStreet) -- Toyota ( TM) and National Highway Traffic Safety Administration (NHTSA) officials are questioning the credibility of a report on a Toyota Prius runaway incident on a San Diego highway, following an initial investigation in which they couldn't reproduce the event in their tests; the California Highway Patrol and the driver's attorney, however, are standing by him.

The findings regarding 61-year old James Sikes' report on his runaway 2008 Prius experience on a San Diego highway were documented in a draft memorandum by congressional investigators. Sikes' car pictured above had sped up to 94 mph before being rescued by patrol officers who helped him bring the car back down to 50 mph and eventually to a halt, says AP.

"So, in this case, knowing that we are able to push the car around the shop, it does not appear to be feasibly possible, both electronically and mechanically, that his gas pedal was stuck to the floor and he was slamming on the brake at the same time," said David Jusko, a Toyota employee and hybrids expert, who was quoted in the memo obtained by The Detroit News.

According to the memo, two Toyota technicians and NHTSA technicians looked into the Prius and congressional personnel and another Toyota field technician looked at the test Prius.

"On our test drive, the field technician tried to duplicate the same experience that Mr. Sikes experienced. After about two hours of driving he was unsuccessful," the memo said, according to The Detroit News. "Every time the technician placed the gas pedal to the floor and the brake pedal to the floor the engine shut off and the car immediately started to slow down. NHTSA and Toyota field representatives reported the same results with the 2008 Prius owned by Mr. Sikes."

James Sikes' lawyer John Gomez, shot back at report and defended Sike's credibility.

"I don't put a whole lot of stock in their explanation," Gomez said, according to AP. "It's not surprising they couldn't replicate it. They have never been able to replicate an incident of sudden acceleration. Mr. Sikes never had a problem in the three years he owned this vehicle."

Meanwhile, the California Highway Patrol stands by its belief that Sike's experience was real and that no part of it was fabricated.

"Unless they can completely disprove Mr. Sikes, we're done," Brian Pennings, a California Highway Patrol spokesman said, according to AP. "It doesn't sound like they can do that."

Meanwhile, Toyota announced at a press conference Monday that its preliminary investigation on Mar. 10 and 11 of the alleged runaway vehicle indicates that "the driver's account of the event is inconsistent with the findings of the preliminary analysis."

Toyota cites numerous findings that support its belief that there should be further investigation of Sikes' account of events tied to the runaway vehicle allegation, including: Toyota's claim that the accelerator pedal was tested and found to be working normally with no mechanical binding or friction; the fact that the front brakes showed severe wear and damage from overheating; and that a Toyota carpeted floor mat of the correct type for the vehicle was installed but not secured to the retention hooks.

-- Reported by Andrea Tse in New York


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