It's something many of us do before heading out the door, but it could put you at risk to be targeted by thieves.

The act of starting your car in the morning to warm it up is sometimes called puffing.

"I go and start the car up and go back in the house," said one Mid-Michigander on Tuesday. And so do a lot of people, and the police say it is a bad idea. 

"We caution citizens about leaving their cars running unattended, whether it be in a driveway or in a parking lot," said Saginaw Township Police Chief Donald Pussehl.

It's a new trend called "puffing." Cars thieves see a puff of smoke coming out of your tailpipe and if no one is around, they will steal your car. Pussehl says there are ways to stay warm and still protect yourself from car thieves. One of those ways is to use a remote start.

Robert Orr is the store manager at Duke's Car Stereo in Saginaw Township. Orr says an automatic starter device is an easy way to protect yourself from thieves. They cost anywhere from $99 to $400.

"If someone was to get in the vehicle and steal it, as soon as they put it in gear, you first have to put your foot on the brake and once they do that the vehicle stalls," explains Orr. "The brake essentially disengages the remote starter and then the regular ignition takes over."

Pussehl says leaving your car running and unattended is not only an open invitation to thieves, it's actually illegal. "A person could receive a traffic citation for that," said Pussehl.

While warming up your car may be illegal, it's sure nice to commute in a vehicle that's warmer than an ice cube on those early Michigan winter mornings.

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