If you start to notice a stinky smell coming from your car's exhaust system, the stench may be the least of your worries. Pungent exhaust smells can arise from a multitude of issues: it may be as simple as a worn-out muffler, or it may be as severe as burnt-out seals inside of your engine.
The Smell Can Be Poisonous
Even a mere leaky pipe can be a serious issue. Carbon monoxide and other dangerous gasses are constantly being routed from your engine to the rear of your car. A leak in the wrong place can let those gasses pass into your car's interior, creating a health hazard for you and your passengers. That's why it's important to have your exhaust system inspected by a reputable automotive shop and repaired immediately if you notice any strange smells.
The Stench May Be the Smell of Pollution and Wasted Gasoline
If there are no leaks in your exhaust pipes or gaskets, the next common culprit is a bad catalytic converter. Your car's catalytic converter is responsible for burning off the majority of pollutants in the exhaust gasses before they're released into the air, thereby making your engine drastically more environmentally friendly. If the catalytic converter wears out, all of those nasty gasses will be expelled directly into the atmosphere.
Additionally, a faulty catalytic converter can rob your engine of efficiency. Modern cars use oxygen sensors within the exhaust system to monitor the output of the engine. A worn-out catalytic converter can confuse the sensors by flooding them with excess gasoline and other chemicals that are expelled during the engine's combustion process. To compensate, your engine will electronically modify the parameters of its fuel injection and air intake system, which will rob it of fuel efficiency and horsepower.
The Issue May Be Originating in the Heart of Your Engine
If your exhaust system is fully functional and undamaged, the stench may be the result of your engine burning fluids that it isn't supposed to. For example, worn-out piston rings and other gaskets can let oil seep into the engine's cylinders where it gets burned up during the combustion process. That can create an odd exhaust smell as well as white smoke emitting from your muffler. Another common example is a faulty intake manifold gasket, which will allow coolant to leak into the engine cylinders.
If you don't have the faulty gaskets replaced, the problem will worsen over time and potentially cause your engine to break down entirely. Avoid getting stranded on the side of the road and stuck wit huge repair bills by nipping the problem in the bud as soon as you notice the exhaust stench. Contact an auto repair service soon if you are having trouble.