The catalytic converter. It is one of those least known and valued parts of a car. But do you know that this little known and well-hidden part of your car plays a gigantic role in saving the planet? Not making sense? No problem, let’s take it from the top.
What is a Catalytic Converter?
A catalytic converter is a simple device used to convert harmful gases produced by the combustion engine into less harmful emissions before they are expelled into the air through your car’s exhaust system. It does this by using two metals, palladium and platinum to catalyze (speed up) a redox (reduction and oxidation) reaction that converts the said toxic fumes into harmless gases such as – CO2 and water.
Catalytic Converter Failure – The Causes
Catalytic converters are actually among the strongest parts of your car, they can last the entire life of a car. But they do fail, and it’s important for you to understand why. And to understand that, you need to remember that the catalytic converter is a hub for chemical reactions, so the more the reactions take place (meaning more mileage being put on the car), the more the catalytic converter wears out.
But the most common causes of the catalytic converter failing can be summed up under one umbrella – an engine that is not burning fuel properly. For example, worn out spark plugs, leaking exhaust valves, or even a faulty starter can allow unburned fuel to pass into the exhaust system where it can be ignited and damage the catalytic converter. These are minor faults that can be easily fixed, but there are some other major faults that can lead to the catalytic converter getting damaged. For example, worn piston rings, a jumped timing chain, or a head gasket or intake manifold that is leaking (can lead to oil or coolant to cover the catalytic converter) can all lead to the catalytic converter failing.
This ultimately means that if you discover that your catalytic converter is faulty, you have to trace the underlying cause and fix it, otherwise, you will end up replacing your “cat” again, and again. So how do you tell if your catalytic converter is faulty? Good question. And I believe I have some pretty good answers for you too.
Signs of a Faulty Catalytic Converter
Although a faulty cat converter may not be an obvious fault to diagnose, there are a few simple ways you can diagnose a faulty catalytic converter. Let’s take a look at the, shall we?
1. Heed Your Warning Lights
One of the most common triggers of the check engine light is a “wrong” oxygen reading, and that on its own can be the result of a faulty sensor or a broken catalytic converter. That is why it is unwise to ignore the check engine light like most people do. Just because your car is still moving doesn’t mean the warning is insignificant. The easiest way to find out what is triggering the check engine light is by using a code reader, either at home or at your local garage.
2. A Rattling Noise Under Your Car
This one is from personal experience. When a catalytic converter fails, it sometimes breaks apart into many small pieces. These pieces make a rattling noise in your exhaust when accelerating or decelerating. This is because the pressure in the exhaust system changes, and the movement of causes the pieces to hit against the walls of your exhaust, causing the very irritating rattling noise. These small pieces can also pass through the exhaust system and cause greater damage to your engine.
3. Poor Engine Performance
Another indicator of a failing catalytic converter is poor engine performance. This means your fuel economy will increase due to wrong oxygen/fuel ratios being mixed in the engine, a result of a faulty catalytic converter and oxygen sensor situated just after the cat. Your engine will become underpowered and will struggle to accelerate.
4. Failed Emissions Test
Many a time when a car fails an emissions test, the culprit is the catalytic converter. The reason is simple. Because the catalytic converter is faulty, it can’t convert the toxic emissions in the exhaust into the harmless gases it should. Next time your car fails an emissions test, check the cat first.
What to Do When a Catalytic Converter Fails
I know I’ll get a lot of flack for what I’m about to say but I’ll say it anyway. When your catalytic converter fails, don’t replace it with a straight pipe. It may be cheaper than getting a newer catalytic converter but in the long run, it will cost the earth – literally.
With the advancements in technology, catalytic converters are becoming cheaper and easier to replace, so you have no excuse for not replacing yours.