The great-grandmother said the man hit her twice in the head with his gun.
"I reached over, was going to get my pocket book, and in the meantime, he came around and to me and got in my car," she said.
Before she could ask what he was doing, she said, he started to attack.
"When she inquired what he was doing, he pointed a pistol at her and hit her with it, struck her with the pistol," said Geoffrey Gilland, with the Athens-Clarke County Police Department.
Police said the gunman grabbed her purse, pushed her from the car and drove off. But right before he left, he gave her a warning.
"He said, 'You don't want to die today,' and I said, 'No I don't,'" the woman said.
A regular customer of the car wash said the carjacker needs to be behind bars before he can target another victim.
"To do that to an elderly person that way, that's horrible. That really is," Jerome Taylor said.
Police said the victim's car has an "Army mom" sticker on the back window. The victim's late husband was a former police officer.
"I guess I'm thankful to be alive, 'cause he could have shot me," she said.
A $1,000 reward is being offered by CrimeStoppers to catch the criminal.