Catalytic converter’s failure symptoms

The catalytic converter is a valuable part, even after it fails. And many vehicle owners know that it is most profitable to sell an out-of-service spare part through the website

Replacing a catalytic converter is expensive. Therefore, selling the old part will help a little to offset the costs.

But how do you know that the exhaust converter does not cope with its functions and it is time to replace it with a spare part? In some cases, the engine will not start at all. Then, in any case, you have to go to the auto repair shop.

But if the catalytic converter has just begun to fail, a number of signs will indicate this. Consider the main symptoms that foreshow a failure.

Loss of performance and increased fuel consumption

One of the most obvious signs of a clogged catalytic converter is a loss of vehicle dynamics and performance. This effect is especially sensed during acceleration or while driving uphill. The vehicle reacts more slowly to the gas pedal and takes a long time to accelerate. And when it comes to going uphill, you have to switch to a lower gear compared to the usual driving mode.

At such moments, it seems that the engine operates under extra load. As a result, the vehicle starts to consume more fuel.

It is difficult to start the engine

When the catalytic converter becomes clogged, starting the engine can be quite a challenging task. In this case, the following situations can be observed:

  • the starter turns, but the engine does not start;
  • the vehicle starts, but after a while it stalls;
  • the engine starts well when it is cold, but after warming up it is difficult to be started.

Such situations are associated with the fact that the catalytic converter is controlled by sensors that control the purification process. If deviations in the indicators are detected, the lambda probe transmits a signal to the onboard computer and the engine is put into emergency mode.

More often, such situations occur when the engine is warmed up because the converter operates only after heating up to a temperature of about 300 degrees Celsius.

Check Engine indicator

The catalytic converter’s failure can be detected through the Check Engine indicator that lights on the dashboard. Under normal conditions, the indicator should go out after the engine is started. If it continues to light, then there is a possibility that the exhaust converter malfunctions.

But this sensor may give alerts about other breakdowns as well. For example, a flashing Check Engine indicator may warn of a problem with the ignition system that could damage the catalytic converter.

Rattling sound under the vehicle bottom

If, while driving, an unpleasant rattling sound is heard from under the bottom, there is a possibility of mechanical damage to the catalytic converter. If it intensifies when running at a neutral travel position, you should immediately contact a car repair shop. Broken-off fragments of the converter can get into the piston system of the engine, which in turn will result in the need for an overhaul of this expensive unit as well.