Exhaust Smell In Car - Service Answers at Hanson KIA

The smell of exhaust is never one that you want to smell in your vehicle's cabin. Exhaust gases contain toxic compounds like carbon monoxide, which could put your health or even your life at risk. Now, before you get too worried, you should first check and make sure the smell is coming from your vehicle, and not the exhaust of another car in front of you. If the smell remains when you're no longer behind that same vehicle, you should park your car as soon as possible and call for a tow to an authorized service center.

The smell of exhaust may be tinged with other scents, and these can give you a hint as to what's causing the problem. On this service information page, we'll walk you through four potential causes and what they might smell like.

The exhaust system runs the length of your vehicle and is susceptible to damag

4. Bad Catalytic Converter

The catalytic converter is an important part of your vehicle's exhaust system. It takes the more harmful compounds in exhaust gas (like hydrocarbons) and converts them into less harmful ones (like carbon dioxide and water). If the catalytic converter is broken, your exhaust may smell like sulfur or rotten eggs. Unfortunately, a broken catalytic converter cannot be repaired, and will need to be replaced.

3. Damaged O2 Sensor

Your Kia has at least two oxygen sensors: an upstream sensor located in front of the catalytic converter and a downstream sensor located behind it. These two sensors will measure the level of oxygen in your car's exhaust, and will let the computer know how to adjust the air/fuel ratio for the most efficient combustion. If one (or more) of the oxygen sensors in your car is damaged, your engine may be using too much fuel and not enough air. This could also cause the exhaust to smell like sulfur or rotten eggs, so the presence of this smell alone isn't enough to determine what the underlying problem is. However, it could also cause the exhaust to smell like gasoline.

A damaged heater core can cause a smell similar to exhaust in your cabin

2. Heater Core Problem

Though it's not technically the smell of exhaust, this one often gets reported as an exhaust smell. If the heater core in your vehicle is damaged, it might cause the smell of burning coolant to enter your cabin. Though this is similar to an exhaust smell, it's notably sweeter.

1. Exhaust System Leak

The exhaust system is designed to take the exhaust gases (which are harmful to your health) and take them safely away from you. A leak in any part of the system may mean that this process is not happening the way it should, which could put you in danger. In addition to the smell, an exhaust leak may also cause strange rumbling or hissing noises, reduced gas mileage, and other symptoms. But if you ever smell exhaust in your car, stop driving and have it towed to a dealership. Driving with exhaust gases in your cabin is unsafe.


Hanson Kia

2300 Carriage Loop SW
Directions Olympia, WA 98502

  • Sales: (360) 339-5079
  • Service: (360) 339-5079
  • Parts: (360) 339-5079