Clogged catalyst: symptoms, troubleshooting and recommendations

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

The catalyst in a modern car is an important part of the exhaust system. This element does two things. This is the cleaning of exhaust gases before they enter the atmosphere, as well as reducing the resistance for their exit. The power that the engine will produce depends on the catalyst. If suddenly the car can no longer go as fast as before, or fuel consumption has increased, then there is such a problem as a clogged catalyst. These symptoms can be with other malfunctions, but most often they are associated with the catalyst. Consider other signs of contamination of the element, as well as ways to solve problems.

Main signs of element failure

Drivers, even with little experience, will be able to determine without any problems that there are malfunctions in the exhaust system. If the exhaust gases do not flow well through the system, this will inevitably affect the behavior of the car and the sounds of the engine.

Loss of power

The car will have a hard time accelerating.

In this case, this problem willonly be felt for a while. This period depends on how heavily contaminated the catalyst is and whether it is in good condition. Symptoms of a clogged catalytic converter are slow acceleration in low gears. If you go to a higher one, then the motor will work in its normal mode. Also, when driving, the driver may get the feeling that there is a very heavy load in the trunk, which does not allow enough acceleration.

Chek Engine

This is also one of the symptoms that could indicate a catalyst.

For example, if the part is heavily clogged, then the ECU will light the lamp. In this case, the driver must check the malfunction. If the car is equipped with an on-board computer, then an error message will be displayed on it: "Clogged catalytic converter". The symptoms are the same - loss of power, problems with the efficiency of the engine. This is reported by error P0420.

High fuel consumption

Due to excessive contamination of the catalyst, fuel consumption can increase significantly. It is worth paying attention to the fact that the consumption will only report problems in the exhaust system if there are other symptoms of a clogged catalyst - loss of power and slow acceleration.

Why the element fails

A car converter cannot fail just by itself. If there are problems with this part or the engine does not want to gain momentum and has lost its power, then this indicates that the system has a deformed or clogged catalyst.

These symptoms may occur for some reason.

Poor quality fuel

If the mixture of gasoline and air does not completely burn out in the engine cylinders, then combustion ends in the catalyst or in the exhaust manifold. Then the main parts of the exhaust system are melted. The combustion products settle in the converter and prevent the gases from passing at the required speed. As a result, the system just clogs up.

Poor quality catalyst

Automakers supply vehicles with quality parts and consumables. But if something in the car changed, then it’s not a fact that the owner was sold high-quality spare parts. If a low-quality or non-original converter is installed in the car, then there is a big risk that the catalyst cells are too small. Due to their insufficient size, they are easily clogged with combustion products.

Often, all signs of malfunction and symptoms of a clogged catalyst occur in American cars that were previously operated in the United States. In the United States, gas stations sell better quality gasoline, which leaves a minimum of unburned substances during the combustion process. Catalysts in such cars with small honeycombs - in Russia they die in the shortest possible time.

Problems with engine operation

This is another reason. As a result, the owner gets a clogged catalyst. Symptoms of some problems in the engineare imperceptible, and it is very difficult to say as accurately as possible what exactly leads to the growth of fuel combustion products in the exhaust system without serious computer diagnostics. The "brains" of the car are checked and all error codes are read.

Bad roads

If the car is regularly used on poor quality roads, then there is a big risk that it can be deformed. Even a slight blow is enough for the cells to begin to collapse or deform. In order not to replace an expensive part, it is better to carefully cross obstacles, such as speed bumps.

Diesel engines

There is no catalyst on such power units. There is a particulate filter instead, it performs the same task as the catalytic converter in a gasoline engine. Another difference is the price. A particulate filter will cost three times as much as a gasoline element.

The symptoms of a clogged catalytic converter on a diesel are similar to those that owners of gasoline engines may experience. This is a loss of power, the engine refuses to start, increased fuel consumption.

How to test a catalyst on a car

You can also diagnose this part yourself, provided that you have the necessary knowledge, skills and equipment. Also check the neutralizer in any service. There are three diagnostic methods.

Visual way

A simple inspection is supposed here. Problems in the operation of this system can be identified simply by looking athim. If there are various deformations on the body, there is a high probability that the cells are damaged. It is impossible to find out that the catalyst is clogged from the outside. It will have to be dismantled.

The problem is the difficulty of dismantling the task. It is necessary to drive the car onto a flyover or pit. In addition, each car has its own installation principle. Also a common problem is the sticking of the retainer that holds the converter. Therefore, most often dismantling is carried out only for replacement using a grinder.

If the part was removed, then it is examined for gaps. If the device is clogged with dirt, it can be cleaned, but it is better to replace it. It must be remembered that such an inspection can be carried out not on neutralizers. Therefore, there are other ways to determine if the catalyst is clogged.

Back pressure test

This method does not require dismantling. The principle of the test is to measure the pressure of the exhaust gases. The data is then compared with ideal parameters. To carry out the operation, you need a pressure gauge and an adapter to include it in the system. The car should be installed on a flyover or pit. Next, the first lambda probe is removed, and a pressure gauge is connected instead. It is important to connect it to the system so that everything is as tight as possible.

Next, start the engine and raise the speed to 2500-3000, and also fix the pressure gauge. If the pressure is approximately 0.3 kgf/cm², then everything is fine with the converter. If 0.35kgf/cm², then (if the motor has not been modified) you should pay attention to it. When the level is 0.5 kgf/cm^{2 and above, the converter is faulty.}

In conclusion

Usually in modern cars, the computer itself informs the driver if the catalyst is clogged. What symptoms will be on cars without a diagnostic system - described above. The best solution to the problem is replacement. But it is very expensive, so many service stations offer to install a flame arrester.