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Catalytic converters: causes of failure

Despite the fact that some users forget about the existence of such a vehicle part as a catalytic converter, this unit of the exhaust system is very important. Purification of exhaust gases is not the only process that depends on it. It is also important for the performance of the engine. As a rule, this spare part is remembered only when it has failed. As a matter of fact, this is not good news since a new catalytic converter is very expensive. Nevertheless, the exhaust converter remains valuable even when it is out of operation. For example, you can estimate the average cost and sell a BMW converter at

Let us look at the main symptoms of the catalytic converter failure and the reasons behind it.

Symptoms of the converter failure

The catalyst fails instantly only in case of serious mechanical damage due to impacts. But in most cases, the symptoms of a malfunction appear gradually. The main features include the following:

  • loss of dynamics. The vehicle picks up speed with difficulty, and the usual power is not enough on overtaking and when driving uphill;
  • the Check Engine appears on the dashboard. The indicator does not go out after starting the engine. This light is activated for some other problems as well. But often its appearance is triggered by malfunctions of the catalytic converter. As a rule, in such cases, the error code P0420 is displayed;
  • fuel consumption is noticeably increased due to the load on the engine. If at the same time there is a loss of dynamics and an increase in fuel consumption, it can be the sign of the catalytic converter malfunctions with a high degree of probability;
  • the engine is hard to start or it stalls a few seconds after starting. This symptom is the most obvious sign of problems with the exhaust gas converter. Most often, problems with starting the motor are observed when the engine is warmed up.

It is recommended to immediately contact a car workshop to diagnose the malfunction if any of the above symptoms are noticed.

Reasons for the converter failure

The main problems in the operation of the catalytic converter are associated with clogging of the channels, which results in the decrease of the throughput of the exhaust system. Deformations and damages to the integrity of the internal ceramic block also lead to breakage. These are the consequences of the following:

  • refueling the vehicle with low-quality fuel;
  • installation of a low-quality catalytic converter during the previous replacement;
  • frequent driving on bad and bumpy roads;
  • clogging of honeycombs;
  • melting of the catalytic layer;
  • mechanical damage;
  • burnout of precious metal coating.

It is recommended to fix any malfunctions of the catalytic converter as soon as possible. This will help to avoid overhaul of the engine and other critical systems. The converter itself can be replaced with an original part or its analog. There is another option - the spare part can be removed and a flame arrester can be installed in its place. But in any case, you should not throw away the old catalytic converter because it can always be sold profitably through AutoCatalystMarket.

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