by Richard Rowe
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What Happens When Smoke Gets Into Your Car? The main problem is probably that you are still sitting in the car instead of running for your life, or at least looking for the nearest fire extinguisher. But joking aside, a little smoke coming through the ventilation system doesn’t have to be fatal to you or your car; It all depends on what you are smoking and where it comes from.
Identify the smoke
The first thing to do is identify the type of smoke and the best way to do this is by smell. Most people know the smell of burning oil; it smells like an asphalt parking lot on a hot day, roofing tar, or driving on a highway paving construction crew. Electrical wiring burns with an incredibly acrid, eye-watering stench. It’s one of those smells that, if you don’t want to jump out of the car, at least it’s impossible to ignore. Coolant usually has a sickly sweet smell, enough to stop you from drinking ice cream for a week.
Your next clue to the source of your smoke has to do with the thickness or density of the smoke. A slight puff and occasionally a hint of oil smoke with the AC fan on low will usually indicate a minor oil leak in the engine compartment. A constant visible stream of smoke tells you that the source is very close to the blower or air inlet, or within the duct itself. If the smoke rises high enough to visibly fill the cabin, your car is likely on fire. Take it out and sell it to someone you don’t like.
Fresh air versus recycled air
This test will give you an idea of whether the fountain is inside or outside the cabin. Placing the air conditioner in the “ventilation” position brings in fresh air from outside, while turning on the air only recycles the air already present inside the cabin. This is a particularly useful trick for locating coolant leaks and finding out if the odor is coming from the engine compartment or the heater core. Electric smoke drawn in through the fresh air vent is likely coming from the engine compartment, perhaps as a result of a wire touching something hot like the exhaust manifold.
Electrical odors and mist
If you notice an electrical odor, particularly one with a hot coppery tinge, with the air in both recycling and vents, you may have a faulty fan on your hands. If you only smell electrical insulation with recycled air, you probably have a short in the wire behind the dash. If you have an odorless “smoke” that only occurs with the air conditioner on high, congratulations, you have an air conditioning system that blows cool enough to condense moisture into vapor and blow it into your face.