What To Do When Your Catalytic Converter Fails
It wasn’t until 1976 when the installation of a catalytic converter was mandated by the government. This was done in response to concerns regarding the increasing volume of pollution in the atmosphere. As part of your car’s emissions control system, the cat converter helps to minimize the level of harmful exhaust gases that escape into the air.
The location of the component varies by make and model. In some vehicles, it is attached to the exhaust manifold. In others, it is positioned between the exhaust manifold and the muffler. Still other cars are equipped with more than one cat converter positioned in various places along the exhaust line.
In this article, we’ll explain how this component works, and what happens in the event it fails. We’ll also offer a few suggestions for replacing it.
Purpose Of The Catalytic Converter
Your engine’s combustion cycle produces exhaust gases that are pushed from the cylinders into the exhaust system. These gases contain harmful elements, including carbon monoxide, hydrocarbons, and nitrogen oxides (NOx). Prior to 1976, most of these elements would leave the tailpipe, and escape into the environment. Today, they enter the catalytic converter.
This component essentially converts the harmful gases into harmless ones. By the time exhaust gases exit the tailpipe, they are relatively safe.
How The Component Works
The catalytic converter is made of stainless steel. Exhaust gases enter the component through one end, and exit the opposite end. It operates at high temperatures, sometimes reaching 1,600 degrees Fahrenheit. A heat shield protects nearby components.
Several honeycomb beds are coated with platinum, palladium, and other metals. These metals interact with harmful agents in the exhaust gases, binding to them and preventing them from escaping. This allows the gases from the engine to leave the cat converter en route to the tailpipe, abandoning elements that would otherwise prove harmful to the environment.
If the engine is performing well, the catalytic converter can do its job without problems. However, if the air-fuel mixture in the combustion chambers runs rich, the component will be forced to work harder to clean the gases. This can overtax the part, causing it to operate at an excessively high temperature. In some cases, it will actually start to glow due to the heat. If this condition persists, the catalytic converter will eventually fail.
What Happens When The Catalytic Converter Fails
Failure of this component will usually trigger the check engine light on your instrument panel. The powertrain control module (PCM) will log a diagnostic fault code in its memory. You might also hear a loud clattering noise coming from the undercarriage, and notice an unpleasant odor with traces of fuel and coolant. These signs are difficult to miss.
Because the cat converter is no longer able to clean the exhaust gases coming from your engine, your vehicle’s emissions will increase substantially. Consequently, your car will fail a smog check (i.e. emissions test). In rare cases, the part will become so clogged that gases are unable to escape the exhaust system. This can impact the performance of your engine.
Replacing The Component
Replacing the converter is a job best left to a trained auto technician. The vehicle must be lifted in order to gain access to the part. Also, a lot of cars require catalytic converters that are specific to a particular make and model.
Another reason to allow a mechanic to do the job is because failed converters are usually due to another problem. Such issues must be diagnosed and fixed lest a replacement also burn out prematurely. For example, if the component fails because the engine is running rich, a mechanic can troubleshoot the rich air-fuel mix to prevent a recurrence.
Few people consider the importance of their catalytic converters to the smooth operation of their vehicles. If the part fails, have it replaced as soon as possible.