By Howard Breuer
December 10, 2013 10:15 AM
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The limited-edition Porsche Carrera GT that Paul Walker and Roger Rodas crashed in was an unusually powerful and intricately designed sports car – and one of Rodas’s favorites, an auto technician who maintained and rode in the car tells PEOPLE exclusively.

Jason Doornick, 25, who serviced the high-performance vehicles at Always Evolving, Rodas’s custom car shop in Valencia, Calif., says he conducted a 350-point inspection of the 2005 Porsche a couple of weeks before the single-car wreck that killed both men. He says the car had only a few thousand miles on it and seemed fine.

“As far as I know, I was the last one to touch it,” Doornick tells PEOPLE.

However, he says, he can’t rule out mechanical failure as a cause of the crash because the GT had specialized housings that blocked anyone other than a Porsche mechanic from accessing the engine and other key areas. He says even the lug nuts, which were thick like the bottom of a wine bottle, required a special Porsche tool.

“I’m not afraid that I overlooked a broken line or something like that,” Doornick tells PEOPLE. “Everything on that car was built to be aerodynamic and extremely inaccessible.”

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Doornick says he started working at AE roughly a year ago, after he and Rodas bonded over their love of Ford Mustangs, which are Doornick’s specialty. Of the roughly 47 cars in AE’s showroom, Rodas’s favorites were some of the Mustangs and this GT, a flashy, heavy, 610-horsepower race car with an engine larger than that of a Bugatti Veyron, says Doornick.

Doornick adds that he’s moving on to another muscle-car shop in Valencia because he only worked at AE to be around Rodas, whom he considered a friend and an inspiration.

Doornick says Rodas was a Salvadoran immigrant who came up poor and “built an empire” (Rodas was also a sought-after wealth adviser). Although Rodas wasn’t technically a professional race car driver, Doornick says, “He was an expert. Why I loved him so much was he knew the car from front to back before he got behind the wheel. He knew what the car was capable of. He was very smart.”

Because the GT and many of the other cars in the showroom sat for so long, Doornick says, most of the maintenance involved simple things like keeping air in the tires and a good charge on the batteries.

“Batteries were always an issue, and I was put in charge of all these cars to make sure they drove well,” Doornick says. “That battery had to be replaced … because it sat for so long.”

Like others who are familiar with Rodas and the car he was driving, Doornick says he’s stumped by what could have caused the accident. Standing about 100 feet from the accident scene last week, he pointed to what appeared to be a trail of power-steering fluid. But even if the car had lost its power steering, it still shouldn’t have been too hard to control, especially for Rodas, Doornick says.

Sheriff’s investigators have said speed was a factor in the crash, but they are still trying to determine how fast the car was going and whether other factors contributed to the accident.

Despite all its speed and flash, Doornick says if he had $440,000 to spend on any sports car, it definitely wouldn’t be this GT. “It has an excessive amount of power that you don’t need for an open road,” he says, noting that it’s also not the safest race car because it’s very crammed and lacks a roll cage.

“It was here to make people’s jaws drop and to give them an appreciation for how much power you could command under your feet,” Doornick said.

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