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Can a Bad Catalytic Converter Damage Your Engine? (Answered)

The importance of a catalytic converter in a car is often underestimated, until of course, one goes bad. A bad catalytic converter can cause several issues, stick with us to figure out if a bad catalytic converter can damage your engine. 

Can a bad catalytic converter damage your engine?

A bad catalytic converter could damage a car’s engine because it would fail to regulate the increased emissions. The engine in turn is unable to manage the increased backward pressure from the fumes. This may cause problems like a slow start, lagged acceleration, and noisy or jerky drives.

As you might already know, the catalytic converter may be one of those parts of a car, which, if it stops working or gets worn out, needs to be replaced or repaired immediately. 

This is because a catalytic converter is primarily responsible for converting harmful fumes into less harmful ones. You might be thinking how does a conversion of gasses affect the engine? 

As engines give off large amounts of harmful gasses, the catalytic converter changes toxic gasses like carbon monoxide into vapor and less harmful gasses. Not only does this keep the airflow in the right direction, but the emission is also reduced. 

When a catalytic converter is not working, the engine light would flash a trouble code that indicates that something is wrong with the converter. 

Other than that, due to the uneven fume pressure and restricted airflow, the engine may run the risk of getting overheated. This in turn may cause a misfire, particularly when you continue to drive a car with a bad catalytic converter. 

A bad catalytic converter can affect the engine in more than one way. Due to gradual damage to the engine, the performance of the car also becomes sluggish. You can expect to hear rattling noises from the engine if your converter is broken or worn out. 

On the other hand, the engines start to stall and create problems every time they start. The unburnt gasses may cause the engine to choke and shut down. Jerky movements and increased fuel consumption are some of the problems caused by the effects on the car’s engine. 

How does a bad catalytic converter affect the engine?

A bad catalytic converter can affect the engine by the following means –

Acceleration may be stalled or lagging: 

Whenever a car’s engine is affected, the first symptom is a lag in the acceleration. In most cases, due to a compromised power of the engine due to a bad catalytic converter, drivers are unable to accelerate their cars most efficiently. 

A clogged catalytic converter or a damaged one would mean that the combustion system is not your engine and is unable to manage any pressure buildup. 

This restricts the free fume movements, hence choking the converter. The result is often lagging or slow acceleration and even lost power. 

Problems with starting: 

If your engine is affected, the first signs that signal you about it are always the way your car is started. 

A bad catalytic converter would mean that your car’s engine is unable to burn fuel as much as it should. This mainly happens when the catalytic converter is clogged. If an engine is unable to burn efficiently, a backward compression is created. 

Without proper pressure from the front and an additional one from the back, the engine would fail to eliminate the created exhaust fumes. This would hence, cause the engine to start only for a few seconds before it dies due to the increased exhaust fumes pressure. 

Noises from the engine: 

If you have ever noticed rattling noises coming from your engine, you should never ignore them. This is because the rattling noises may be a sign of a damaged catalytic converter. 

This in turn is a sign of bigger problems. The mesh inside of a catalytic converter is a honeycombed shape, and a damaged mesh could mean that your engine is getting affected directly and hence making the noise. 

Engine would overheat or misfire: 

The root of any overheating or misfiring issue in an engine occurs when the engine is unable to perform proper fuel combustion. 

Other than that, if the flow of oxygen is not smooth and the airflow becomes restricted, you can expect your engine to heat up quickly. All this is caused by a damaged or clogged catalytic converter as well. 

Since the converter is not working and there are large amounts of unburnt gasses building pressure, the overheating can lead to an engine misfire.

Engine emission may be too high: 

Since a worn-out catalytic converter would not be able to emit all the burnt gas, you would expect to see high emissions from the engine. 

An increase in engine emission means you would be able to notice more black smoke around your vehicle, every time you try to start or accelerate. 

Can a bad catalytic converter cause the car to shut off?

A bad catalytic converter can have several effects on the engine, some of which may be difficult to fix and hence would need a complete converter replacement. It can also cause a car to shut off, even in the middle of the road

Although this happens when the initial signs of a bad catalytic converter are ignored, a bad catalytic converter would not be able to regulate the fume or sir pressure. 

With unmanaged air pressure in the engine, it may be unable to create a free flow of fumes, causing the engine to choke. This is when a car may shut off. A misfiring engine can also cause the car to shut off which again, can be triggered by a clogged catalytic converter 

What happens when you drive your car with a bad catalytic converter?

Having a bad catalytic converter in your car is one thing, but driving with one is another. Several issues can occur when you drive your car with a bad catalytic converter. Here are a few possibilities:

Causing a lot of pollution: 

The primary purpose of a catalytic converter is to regulate fuel emissions and in turn reduce the toxic by-products of the exhaust fumes. 

These byproducts include gasses like nitrogen oxides and carbon monoxide. The converter works by changing these harmful gasses to gasses like carbon dioxide, which are not as harmful to the environment. 

If you have a bad catalytic converter in your car and you are driving with it, the harmful gasses are not being eliminated and instead are dissipated into the air. This is causing the air to get polluted and contaminated the air we breathe. 

Not only that, the black smokes and unburnt fumes also comprise hydrocarbons which affect the ozone layer. 

Damaging your engine permanently: 

When you continue to drive with a catalytic converter that is not working right or is worn out, you are creating pressure on the engine that is not sustainable. 

When a converter is clogged or damaged, it is unable to keep the airflow in the right direction. The decreased burning from the engine also creates back pressure that damages the engine every time you start it or even accelerate it. 

Facing decreased performance: 

When you are driving with a bad catalytic converter, you would know for yourself since the performance of the car would be compromised. 

You could be facing drops in the power of the engine and having issues starting the car. Moreover, your car might even stall mid-road if the engine chokes and shuts off. Other than that, your car would make rattling noises. 

Jerky rides and delayed acceleration are just some of the riding issues you might have to face during the drive as well. 

Getting into legal trouble: 

You may want to check if it is legal in your country to drive with a bad catalytic converter. In some countries, the laws are strict and have made it illegal to drive a car that does not have a working catalytic converter. 

If your car is giving off more smoke and making noises, you may be pulled up for driving illegally. This is because you are potentially threatening the environment and the people with bad pollution. 

How long can you drive with a bad catalytic converter?

Since driving with a bad catalytic converter is never harmful or dangerous immediately, you can drive a car with a bad catalytic converter for as long as the car’s engine does not stop or misfire.

Having mentioned that, it is vital to remember that driving with a bad catalytic converter indirectly and gradually damages the engine and other important parts of the car. Hence it is important to fix a bad converter in the shortest time possible. 

Final thoughts

A bad catalytic converter can damage an engine since it is an important part of the combustion system. When a catalytic converter is clogged or worn out, the conversion of the harmful gasses is hampered. Due to immense back pressure on the engine, the car’s engine eventually becomes damaged.