CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Ooo, ooo that smell

My car smells like something is burning…like when you turn your heat on for the first time in the winter and the dust in the ducts heats up and it smells like it burns off. Today I noticed that it occurred strongly when I turned on the defroster. Blechhh! Maybe a plastic bag is wound up somewhere and burning…simple, therefore unlikely, or maybe some of you have run across this and can solve the mystery. My car is a '99 Saturn, as basic as it gets…standard transmission, no power steering, no power anything, but I need it and the heater here in the frozen north. Thoughts?

The first thing you need to do is determine whether the burning smell originates in the ventilation system or is being drawn in from the outside.

The heater core isn’t hot enough to burn things, so if the smell is inside the car I’d guess it’s electrical.

If the odor starts outside the car, say, under the hood, it could be many different things.

Have you been smelling this for a while, of did it just start today?

I mostly agree with the above, except for the part about “The heater core isn’t hot enough to burn things.” I would have thought that too, but I read before of problems with some cars where leaves make their way into the heater core (from the fresh air inlet in front of the windshield.) I believe there was even a TSB or recall (don’t recall which) on one mini-van because of fires starting from the leaves on the heater core.

If you have a cabin air filter, it may need to be changed.

You might want to remove the blower motor from under the dash to see if there’s any debris in the duct. If there is, and it comes in contact with the blower motor resistor pack, this gets hot enough to burn material.

Tester

Thanks for the replies. It didn’t just start today but has been increasing the last couple months. Today was the first time it hit me hard when I turned on the defrost (as opposed to the floor heat). Until now, I could smell it when I got out of the car, primarily on the driver-side front area. Once I opened the hood and sniffed around everywhere I could but it didn’t seem as strong under the hood. Seems worse in wet weather but that may not have anything to do with it. I don’t remember it in the summer and I don’t ever use the air conditioning.

True, I forgot about that. I wonder if that was the cause of the leaf fires?

You probably have a small oil leak somewhere like one of the valve covers. It leaks onto the exhaust manifold and then burns off. The [air] gasket at the back of your hood may also be bad. I’d have both looked into.
(The defroster draws in outside air from between the windshield and the hood. There should be a gasket to prevent it from drawing in the air from the engine compartment.)

I am losing oil from somewhere, not like i see it on the ground but I was down a quart the other day. I’ll have it checked out. Thanks!