auto maintenance myth

Why does my car heater have a bad smell?

car heater Every vehicle runs on energy and produces heat. They also operate using a variety of fluids, gasoline, mechanical parts and an electric system. In other words, chances are good that your car, truck or SUV will emit some bad odors from time to time. This time of year, people turn on their car heater for the first time in months. To their surprise, many are hit with a bad smell when they expect clean, warm air.

Many things create bad odors in your vehicle. Let’s look at eight of these bad smells and what they possibly mean, starting with your car heater.

My Car Heater Creates a Bad Smell

If your heater creates a bad odor, it can mean any of several problems exist. A burning leaf odor coming from the car heater is most common. So why is your heater producing this burning smell?

Dirty Vents

Your car heater’s bad smell could relate to dirty vents. In fact, you should have your car’s comfort system inspected and serviced on a regular basis, such as when you get a tune-up. This vent system gets dirty, typically accumulating debris, dust, leaves, pine needles and dirt. You may not notice any of this buildup until you turn on the heater and expect warmth, but receive what smells like the air from a brush fire. Take your vehicle into Cloverdale Auto for an inspection and service.

Debris in the Engine

A burning bad smell coming through your car heater can also mean you have debris built up on the engine. When leaves, pine needles and other debris get caught under the hood, they toast from the warmth. Then, when you turn on the heater, this characteristic odor comes through the heating vents. If you sense this smell, pull over to a safe parking area and open the car’s hood. Be careful clearing away any debris from hot elements.

Bad Heater Core

When your car heater core ages, it may require replacement. Signs of problems with this part include a burning smell from the heating vents, foggy windows and overheating engine. A regular comfort system check involves service for the heater core, making this maintenance critical. Otherwise, you can face between $600 and $900 in early replacement costs.

Other Bad Smells Detectable through Your Car Heater

Other bad odors possibly detectable through your car heater include:

  • Sulfur or rotten eggs
  • Hot oil
  • Syrup
  • Burned carpet
  • Burned rubber
  • Gasoline
  • Mustiness

The sulfur or rotten egg bad smell from your car heater can signal problems with your catalytic converter. The odor of hot oil often points to a leaky crankshaft or leaky valve cover. With this smell you can sometimes find oil on the pavement where you park or smoke coming from your exhaust pipe.

A sweet, syrupy smell often signals a leaking radiator, hose or heating system. The rich smell comes from ethylene glycol in coolant dripping on hot engine parts. Not as sweet is the smell of burning carpet, which can relate to worn brakes or a dragging brake. Burning rubber is equally unsweet in odor, pointing to loose hoses or belts.

Sometimes when refueling your vehicle, you spill gasoline. This often causes a gasoline odor to enter your vehicle. But coming through your car heater, this bad smell can mean you have a vent hose or fuel injection line leak.

Finally, smelling a mustiness creeping in through your car heater vents can tell you that there is mold or mildew growth in your air conditioner evaporator. Besides the bad odor, this can trigger headaches, itchy eyes, sneezing, breathing problems and other symptoms of allergies or sensitivities.

Inspection, Maintenance and Repair for All Car Heater Problems

Winter is certainly not the time to have a non-working heater or one that creates a bad odor. Besides being irritating, this odor can signal much bigger problems you need to repair before they grow worse. In Winston-Salem, North Carolina, Cloverdale Auto Service provides inspection to find the source of your heater’s bad smell. We also provide routine service and repairs to get your vehicle back on the road in top form. Call us today at 336-331-3448 to schedule your car heater inspection and maintenance.

Cloverdale Auto Service