An important element of a car's exhaust system is the catalytic converter (catalytic converter). Its task is to reduce the amount of harmful combustion elements emitted into the atmosphere. The average catalyst resource is about 100-150 thousand kilometers. It can run flawlessly longer or less, depending on the quality of the engine, the fuel used and a host of other factors. The clogged catalytic converter must be replaced or attempted to be cleaned. If the catalyst is cleaned correctly, it will be able to work for some time before replacing it.

How Does a Catalytic Converter Work?

In practice, the catalytic converter has the following operating principle:
  • Exhaust gases from the engine enter the ceramic blocks, where they penetrate into the cells, completely filling them.
  • The catalyst metals palladium and platinum provoke an oxidation reaction, as a result of which unburned CH hydrocarbons are converted into water vapor, and carbon monoxide CO into carbon dioxide.
  • The reducing metal catalyst rhodium converts NOx (nitrogen oxide) into normal, harmless nitrogen.
  • Purified exhaust gases are released into the atmosphere.
If the vehicle is equipped with a diesel engine, there is always a particulate filter near the catalytic converter. Sometimes these two elements can be combined into a single design.
How Does a Catalytic Converter Work: image
A catalytic converter spits out H20, N2, and CO2.

Symptoms Of Catalytic Contamination

An experienced driver is unlikely to miss the moment when the exhaust system catalyst will no longer cope with its functions. There are a number of signs that indicate its contamination:
  • Decrease in engine power when the car is moving, slow acceleration;
  • Problems with starting the engine;
  • Unstable idling;
  • Spontaneous shutdown of the motor;
  • Increased fuel consumption;
  • Burning Check Engine light.
Also, if the catalyst is heavily contaminated, the driver may notice that the color of the exhaust has changed. You can check the catalyst for contamination by various methods, but it is most effective to remove it and inspect it visually. If the catalyst "honeycomb" contains resin fragments, combustion products, oil and other "waste" that interferes with the passage of exhaust gases, it must be eliminated as much as possible.

What Can A Damaged Catalytic Cause ?

If the catalytic converter is only clogged with soot, it can still be cleaned. But if you do not pay attention to the problem that has arisen, then at best the car simply will not be able to start one day, or the engine will start, but it will quickly stall. It is worse if the bobbin melts due to soot. It will not be possible to restore the damaged element, then either replacing the catalytic converter or removing it and installing a flame arrester will help to restore the engine's performance. The worst case scenario is mechanical destruction. Honeycomb particles can significantly complicate the passage of exhaust gases through the сatalyst. Because of this, some of the gases can return back to the cylinders, and even with impurities of ceramics. And foreign objects in the cylinders, albeit small ones, can already lead to damage to the cylinder-piston group and the need for overhaul. But you should not always "sin" on the catalyst, it can only be a consequence of the fact that some of the auto systems does not work correctly, or low-quality fuel with a large amount of additives is poured into the car. Therefore, even with the slightest drop in power, you should immediately diagnose the state of the power supply and ignition systems, as well as evaluate the performance of all sensors, and only then check the сatalytic.

How To Unclog The Catalytic Converter

If you ask How Not To Unclog The Catalyst?  Often, in order to save money and time, drivers abandon the idea of ​​cleaning and replacing the catalyst, punching new holes in it or drilling them. Such a solution will allow the engine power to be returned, but the car will have violated the indicators of harmful emissions into the atmosphere. In addition, the noise level from the exhaust pipe, which occurs when the vehicle is moving, will increase. Such methods of "cleaning" the catalyst are unacceptable, and during a long operation of the engine with a damaged filter element, various problems may arise with it. There are several ways to unclog the catalyst yourself. Depending on how dirty the catalyst is, it is advisable to choose one or another method of cleaning it.

Unclogging The Catalytic With Sandpaper

If the combustion products are not strongly and not massively "stuck" to the catalyst filter element, you can remove them using ordinary sandpaper. It is quite simple to do this:
  • You will need to take fine-grained sandpaper and remove the catalyst;
  • Then, carefully, not pressing hard on the "honeycomb", you need to clean off the plaque in a circular motion;
  • When the filter element is cleaned, the remaining dirt is blown out using compressed air.
Important: In the process of cleaning the catalyst with sandpaper, do not overdo it with pressing force. Most often, the "honeycomb" of the catalytic converter is made of ceramic. If you press on them too hard, they risk breaking, and you will need to buy a new catalyst.

Unclogging  Strong Contaminations Of The Catalyst With Chemical Means

If the catalyst is heavily contaminated, you can use "chemistry" to clean it. In car stores, you can find special products for flushing and regenerating the catalyst. If it is not possible to purchase such a tool, carburetor fluid or ethanol will cope with the task of cleaning the filter element. The catalyst should be unclogged with special chemicals in accordance with the instructions. If fluid is used for the carburetor, the cleaning process is as follows:
  1. It is necessary to take a plastic container, a bucket is suitable, in which the catalyst can be vertically;
  2. Next, the catalyst is removed from the vehicle and inspected for damage. If they are absent, you can start cleaning, otherwise you will have to think about replacing the filter element;
  3. The catalyst "honeycomb" is abundantly watered with carburetor cleaner, after which the part is wrapped in rags and placed in a plastic container;
After 20-30 minutes, it is necessary to rinse the "honeycomb" of the catalyst under the pressure of hot water.
Important: Do not perform this procedure in a home bathroom, as the chemicals used in carburetor cleaners can corrode bathroom enamel, sinks and damage other interior items; After rinsing the catalyst with water, dry the part and blow it with compressed air;
Then repeat the procedure from the beginning. If the catalyst is critically contaminated, two cleanings may not be enough. In such a situation, it is recommended to use more powerful cleaning agents (for example, kerosene).

Unclogging The Catalytic Converter Without Removing It From The Car?

The best suitable catalyst cleaning fluid is Hi-Gear HG3270. This tool makes it possible not only to effectively remove carbon deposit, but also to clean the carburetor, the tank of the car from deposits, as well as clean the fuel line. You will observe the following changes to your vehicle:
  • the fuel consumption is reduced;
  • increased fuel knock disappears.
  • reduces the toxicity of exhaust gases;
  • carbon deposits will be removed;
  • increases engine power.
After using the Hi-Gear cleaner, the following positive changes are observed in various vehicle systems:
  • carbon deposits are removed;
  • engine power increases;
  • reduced fuel consumption;
  • reduced toxicity of exhaust gases;
  • increased fuel knock is eliminated.
All these transformations are possible only if only the original product is used to clean the catalyst.

Tips for use Hi-Gear cleaner

Unclogging the vehicle catalytic with Hi-Gear HG3270 will only be successful subject to the following conditions:
  1. Fill the gas tank up to 1/3.
  2. Pour Hi-Gear cleaner into the gas tank.
  3. Fill the tank to 100%.
  4. Operate the machine until the full volume of fuel is used up.
Hi-Gear HG3270: image
One pack of Hi-Gear is enough to fill a 60-70 liter fuel tank.
For maximum effect, it is not recommended to refuel the machine while operating on fuel with an additive. Otherwise, the concentration of the active substance will decrease, which will negatively affect the process of removing deposits formed on the catalyst cells.


The catalytic converter plays a very important role in every car. It reduces the concentration of exhaust gases that are released into the atmosphere. However, sometimes such an element can become clogged. In this case, you can do self-cleaning without any problems.