Bad Catalytic Converter Symptoms


A catalytic converter is a vital part of a vehicle that functions to lower car emissions and pollution. This part is normally found between the engine and the exhaust muffler. It is a metal canister filled with a chemical catalyst, usually a platinum and palladium mixture, and assists to convert the car’s emissions into non-dangerous gasses as they are released into the environment. When this part is damaged, it will indicate some signs which may give the owner a clue of what’s going on. Some of the signs of a bad catalytic converter include:

Reduced performance

This occurs when the exhaust becomes trapped in front of the catalytic converter. It is brought about by back pressure, which affects the functioning of your engine and halts it from breathing. This sudden increase in back pressure can make the engine stall and make the car jerk or feel like there is no fuel.

Check engine light comes on

A bad catalytic converter makes the check engine light to illuminate. The oxygen and air fuel ratio sensors that a good number of latest cars are built to verify the efficiency of the catalytic converter by checking the gas levels in the exhaust. So, when the catalytic converter isn’t functioning well or not catalyzing the exhaust gases well, the check engine light comes on.

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When there is misfiring in the engine system, this can make the catalytic converter to overheat. Also, an exceptionally rich fuel combination will show the same signs. In the situation where there is an extra rich fuel combination, raw fuel enters the catalytic converter and is ignited. The catalyst parts can melt in such circumstances.

Low performance of the exhaust system

At times, the failure of a catalytic converter can be linked to an issue inside the fuel system. A clear sign of this is a restriction in the performance of the exhaust system, showing the melting of catalyst materials inside.

Unusual exhaust odors

If you start to hear some strange or irritating smells, you should be keen and check what the issue is. A catalytic converter failure might cause an unusual and unpleasant smell to emerge. A strong, pungent smell is a sign that the catalytic converter is not functioning well and is probably being flooded with fuel. Ensure that you urgently take your car to be inspected if you detect such an odor. When there are excessive heat and gasses being formed, your vehicle may become unfit for driving. This sign normal follows loss in power and acceleration.

Low fuel economy

If you notice that you are pumping more fuel than ever, then it’s time to get the catalytic converter to be checked by a specialist. This might be connected with a bad catalyst converter that makes you lose fuel. If left unresolved, this will cost you a lot.

Heightened emissions

When you notice that there is a raised level of carbon emissions from your exhaust, then you should take your car to be checked for a bad catalytic converter right away. When there is contamination of the chemical systems inside the catalytic converter, it might perform poorly due to the added substances like antifreeze and motor oil. In such a situation, you will be forced to change the bad catalytic converter in order to fix the issue.

Fuel vapor

In case your car is fitted with a carburetor and you understand how to test the catalytic converter, then you should go ahead and test it. When you find signs of fuel vapor suspended over the carburetor, you can now conclude that there is a clog in the catalytic converter.

If you notice one of the signs above, you should repair your catalytic converter right away. This is important before the issue runs out of hand and forces you to replace the entire catalytic converter with a new one.


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