“Fastest woman on four wheels” Jessi Combs’s fatal crash was caused when one of the wheels on her jet-powered car malfunctioned while she was attempting to beat her land-speed record, according to a report.

Combs, 39, was racing at nearly 550 miles per hour through Oregon’s Alvord Desert on Aug. 27 when the vehicle likely struck an object, resulting in failure to the front wheel, Road and Track reported.

The Harney County Sheriff’s Office determined that the failure “led to the front wheel assembly collapsing,” AutoBlog reported.

Combs, a former host of “Mythbusters,” crashed into a dry lake bed and died from blunt force trauma, officials said.

The automotive legend touted the record for the “fastest woman on four wheels” after she piloted her jet-powered North American Eagle Supersonic Speed Challenger at a speed of 398 mph in 2013.

Video taken moments before the crash showed a bright white plume of smoke trailing her vehicle as she attempted to break the record.

Before the fatal crash, Combs wrote in an Instagram post: “People say I’m crazy. I say thank you.”