Vehicle owners and fire departments across the country are asking BMW to explain how some parked cars could suddenly burst into flames.

An ABC News investigation airing today on Good Morning America, World News Tonight with David Muir and Nightline discovered dozens of incidents in which the luxury cars caught fire even though owners reported they had parked their cars and turned them off.

After initially saying they were unaware of any such incidents, a BMW spokesman says the company has investigated the fires brought to its attention by ABC News and has “not seen any pattern” related to a “product defect.”

For one such owner, Bill Macko, BMW wasn’t just a car. It was an identity.

The 55-year-old small business owner says he had bought seven luxury vehicles from the German automaker since 2000. He was a dues-paying member of the BMW Car Club of America, so he read BMW magazines, carried BMW luggage and wore BMW clothes. He was such a BMW enthusiast that he became, he says, a kind of unofficial brand ambassador, introducing so many new customers to the local BMW dealership that the salesmen occasionally cut him a check for his services.

“I was an aficionado,” Macko said. “I had brought so many people on board to BMWs, it was crazy. Everybody knew that I loved them so much … I mean, I lived the product, you know?”

On the night of Dec. 1, 2015, however, Macko says his 2008 BMW X5 suddenly and inexplicably caught fire as it sat parked in his garage in Olney, Maryland. Macko’s wife had just returned from a short drive, parked the car and turned it off. She entered the house and told Macko she noticed a strange smell in the car, and when Macko walked into the garage to check it out, he arrived just in time to hear a “snap, crackle, pop” and see the car burst into flames.

Macko and his wife ran from the house as the fire engulfed the garage and spread throughout both the lower and upper floors. Dozens of firefighters arrived to battle the blaze, and the Mackos watched, from a neighbor’s yard, as their home burned to the ground.

“You cannot do a thing,” Macko said. “That’s the sad part about it.”

Macko had brought the car in for service at the dealership just days before, so he initially thought the fire had been caused by the new battery the mechanics had installed, but once the fire was out, he got another surprise. He learned he’s not the only BMW owner to be left asking questions in the wake of a mysterious fire that started after the car was shut off.

PHOTO: Bill Macko lost his car and his home when his 2008 BMW X5 ignited in his garage. (Doug Terry) More

Like many car manufacturers, BMW has issued recalls over the years for fire-related problems, but an ABC News investigation launched in collaboration with ABC-owned stations in New York, Los Angeles, Chicago, San Francisco, and Raleigh, found more than 40 fires occurring in parked cars across the country in the last five years involving vehicles that did not have open recalls for fire-related issues.

Fire officials in Westchester County outside New York City told WABC-TV they were stunned when they learned how long a 2003 BMW had been sitting parked before it caught on fire.

“The owner told us that the car had been parked for at least four, three or four days,” Mamaroneck Fire Chief Tracey Schmaling told WABC investigative reporter Jim Hoffer. “Which we thought was a little peculiar.”

According to KABC in Los Angeles, a 2011 BMW parked overnight caught fire last month, damaging the car but sparing the Darth Vader costume its owner Steve Copeland wore in performances at children’s charity events.

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“I had planned to do an event the next day, so Darth Vader's sitting on a mannequin in the front seat, and the police and the fire department thought somebody was in the car when it was on fire, so they busted the windows out,” Copeland told KABC. “A couple of the cops thought it was pretty funny. [Darth Vader] has been through a fire before, if you know the story.”

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