6 Ways to Tell If Your Catalytic Converter Is About to Go Bad
While you may not think about it often, your car’s catalytic converter is an important piece of your vehicle. It is a piece that reduces harmful emissions and, in some states, it can cause your car to fail inspection, meaning you can’t drive until it’s fixed. Not to mention, it can have an impact on the overall performance of your vehicle. Being aware of some of the warning signs that your catalytic converter is about to go bad can save you the heartache of being told your car doesn’t pass inspection. Here are six things to look out for.
1. Check Engine Light Comes On
Now, your check engine light could come on for any number of reasons. It could be as small as a loose gas cap or something as serious as a complete engine failure on the horizon. That said, it can also be a sign that something is amiss with your catalytic converter. Modern cars have oxygen sensors that monitor the efficiency of the vehicle’s exhaust system. If something unusual pops up, the check engine light comes on. You can head to your local auto parts store, like Advanced Auto Parts, and have them scan your car. They’ll be able to tell you if your catalytic converter is the culprit for the light coming on.
2. Reduced Engine Performance
A failing catalytic converter can cause noticeable dips in your car’s power and acceleration. Clogged converters restrict exhaust flow, leading to a buildup of back pressure. This resistance forces your engine to work harder, reducing efficiency and power. You might experience sluggish acceleration, especially during highway driving or while climbing hills.
3. Dark or Sulfur-Like Exhaust Smoke
Visible changes in exhaust smoke are another sign that your catalytic converter is struggling. A bad converter can cause dark or black smoke to exit the tailpipe due to unburned fuel. In some cases, you might even detect a rotten egg or sulfur-like odor, which indicates hydrogen sulfide buildup. This happens when the converter fails to break down toxic gases efficiently.
4. Rattling Noises Under the Car
A rattling noise from underneath your vehicle could signal that your catalytic converter is failing. This noise usually comes from broken or loose internal components, such as the ceramic honeycomb structure that filters exhaust gases. Over time, excessive heat or physical damage can cause these parts to deteriorate. You’ll typically hear the rattling when starting the car or during acceleration.
5. Failed Emissions Test
If your car recently failed an emissions test, your catalytic converter might be to blame. A failing converter cannot properly reduce harmful emissions like carbon monoxide and nitrogen oxides. Emissions tests measure the amount of pollutants your car releases, and a bad converter can cause elevated levels. Failing these tests can prevent you from renewing your vehicle registration in many states.
6. Overheating and Poor Fuel Economy
An overheating catalytic converter is a red flag that something is wrong. Excessive back pressure from a clogged converter can cause the exhaust manifold to overheat. This heat can spread to nearby engine components, risking severe damage. You may also notice your fuel economy taking a hit as the engine struggles to push exhaust gases through the clogged converter.
Don’t Ignore the Signs
It’s important that you don’t ignore the signs that your catalytic converter may be on its way out. Recognizing some of these signs early can save you a lot of stress and even some money. As always, I recommend that you perform regular maintenance on your vehicle. It can help you catch some of these issues early. If you notice any of these things going on with your vehicle, don’t wait until you fail an emissions test to do something. Schedule an inspection as soon as possible. It’ll prevent you from experiencing even worse problems down the road.
Read More
These 9 Cars Have the Worst Exhaust Systems—Is Yours on the List?
Why Your Sunroof Leaks (And How to Stop It for Good)
Drew Blankenship is a former Porsche technician who writes and develops content full-time. He lives in North Carolina, where he enjoys spending time with his wife and two children. While Drew no longer gets his hands dirty modifying Porsches, he still loves motorsport and avidly watches Formula 1.