Mysterious cigarette smell in nonsmoker's car

Okay, this is creeping me out and I need to know how this could happen. I have a 2005 Mazda 3. Last night I went Christmas shopping, used my remote to lock the door (I heard it beep, so I?m sure it locked). When I came out the interior reeked of cigarette smoke. I don?t smoke, and no one has ever smoked in my car (I?m the original owner). The smell got worse as I drove the few blocks to home. It was still intense hours later. It was cold and very windy while I was shopping, if that matters. How could this possibly happen?

Perhaps someone emptied their ashtray on the cowl at the bottom of your windshield. That’s where the fresh air comes into the car.

I’m Not Sure You’ll Ever Find The “Smoking Gun”.

I had a cigarette butt stick to the botttom of my shoe once and it smelled up my car for a while.

Speaking of cigarettes and smell, there’s this crazy old lady who lives almost a quarter mile from here. Apparently the old man must not allow smoking in the house because day or night, winter or summer she goes out on the porch to smoke, even takes an ashtray. Talk about creeping one out. On a warm night you can smell her lighting up. Smoking must not be as bad as they say. She’s been doing this for years. That’s all she does.

CSA

Have you considered the possibility that you have an electrical problem in the car?
Is it possible that you are smelling “hot insulation”, rather than cigarette smoke?

Once, after the dealer serviced my '84 Chevy wagon for failed canister purge valve, I thought the car had a cigarette smell inside. When I complained, they shampooed the interior for free. Turns out that it wasn’t quite a cigarette smell. The failed valve had allowed gasoline to accumulate in the canister. They had let the car idle for a l-l-l-long time to empty the canister. Long idle let the catalytic converter get way hot, which melted the plastic underside of the carpeting in the rear seat. It stunk for weeks.

Seconding VDCdriver, make sure it’s cigarette, and not something else burning or burned.

The other suggestions here are reasonable, too.

Let’s Hope It’s Not That Dreaded “Burning Rubber” Smell That Nobody Else Can Smell, Eh ?

CSA

Could be one of the HVAC fan resistors is failing, they resemble parts of a toaster. Are all your fan speeds working?

PDV2, To Piggy-Back Your Theory, What About A Piece Of A Leaf Working Through The HVAC Ducts And Burning Up On Those “Toaster” Resistor Coils ?

I’ve had leaf debris and maple leaf seeds come right out my HVAC vents !

CSA