The 20-year-old was taken by helicopter to a burn unit in Fort Wayne after the 3 p.m. accident Monday outside Walgreens at 1816 Franklin St.
Customers heard a "loud pop,’’ then saw clothes inside the woman’s car on fire, according to police.
She ran across the street to a tanning salon and was found by police after leaving through the back door.
She had burns to her head, neck, arms and hands, police said.
According to police, the woman has a history of huffing and recently spent time in a rehabilitation facility.
At first the woman told a firefighter she had been inhaling the vapors from cans of aerosol deodorant. Later, though, she told police she was only emptying the aerosol cans to get rid of the contents after her stint in rehab.
Police said all of her car windows were up and that nearly a dozen aerosol cans were recovered from the vehicle.