Police say that's an open invitation for car thieves, and it's illegal, punishable by an $86 ticket.
"I thought it was kind of a silly law to have," says driver Amy Sheheski. "I understand with the people who are leaving their cars unlocked and make it easy, but they can't steal my car."
That's because she starts her car by remote-control.
"Just press the 'start' button," she says. "You'll see my headlights come on, then they'll go off, and then (the car) starts."
The doors are locked, and there's no key in the ignition. And if someone breaks in and shifts gears or pushes the pedals, the engine stalls.
Amy says this should be the exception to the law, but it's not.
The law says "No person driving or in charge of a motor vehicle shall permit it to stand unattended without first stopping the engine, locking the ignition, removing the key and effectively setting the brake." No exceptions, not even for these remote controls.
"Obviously when this law was written and put in the books, that wasn't even available," said Jim Mattheis of the Tacoma Police Department.
But the police say until the law is amended, these remote starts are illegal.
"But, the way the law reads it talks about 'leaving the car running,' Mattheis said, "And so technically it would still fall under this particular law."
But Mesheski says she'll risk getting the ticket: "I would guess this wouldn't qualify because they can't steal my car, but I'll still keep using it."
But the police warn if thieves want your car, they'll figure out a way to outsmart the anti-theft device.
Police say if people want the idling car law changed, they'll have to get the Legislature to do it.