How to determine that the catalyst is clogged: signs

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:43

The exhaust system is an integral part of every car. Over the years, it has been improved, and now almost all cars are equipped with a catalyst. What is this element and how to determine that the catalyst is clogged? Symptoms of a malfunction and the device of the element - later in our article.

Destination

The full name of the element is the catalytic converter. It serves to reduce the level of emissions of harmful substances into the atmosphere that enter there with exhaust gases.

Where is it used?

This item is applicable to all diesel and gasoline engines with Euro 3 and higher standards. The catalytic converter is installed immediately after the exhaust pipe - behind the exhaust manifold.

Device

An element consists of several parts. These are the body, carrier block and thermal insulation. The second is the main element in this "chain". The block is made of special ceramics, which is not afraid of high temperatures. By design, this part is a set of cells.

They are essentialincrease the contact area of the ceramic "core" with the exhaust gases. On the surface of these cells there are special substances (catalysts). These are palladium, platinum and rhodium. These elements speed up the time of chemical reactions. Palladium and platinum belong to a number of oxidation catalysts. Thanks to them, the hydrocarbons contained in the gases are converted into water vapor; carbon monoxide oxides into carbon dioxide. Rhodium is a reducing element. It converts nitric oxide into harmless nitrogen. Together, all three chemical elements reduce the level of harmful substances in exhaust gases.

Structurally, the block carrier is located in a metal case. Between these two elements is a layer of thermal insulation. An oxygen sensor is also located inside the converter. The main condition for the operation of the catalytic converter is the high temperature of the gases (about 300 degrees). When heated to this level, rhodium, palladium and platinum can trap up to 90 percent of harmful substances that would otherwise enter the atmosphere.

How to identify the problem?

What are the signs of a clogged catalytic converter? There are several symptoms due to which you can find out the malfunction of this element:

• The car has become difficult to start.
• There are gaps in movement, which sometimes disappear.
• The "Check Engine" light is on.

The reasons for the poor acceleration dynamics are explained by the low throughput of the catalyst.

Sometimes it happens that the car is easypicks up speed of 150 km / h and then, stopping, barely accelerates to 60. As a result, engine performance decreases sharply (low cylinder ventilation). The engine is not able to capture a new portion of air, as the exhaust gases cannot exit the system normally - they "get stuck" in the combustion chamber.

Why is this happening?

If you have a clogged catalytic converter, the signs (it doesn't matter if it's diesel or gasoline) of its malfunction may lie in a large amount of smoke in the gases. They contain a certain percentage of oil (this is natural), but when the engine “eats” a liter per thousand kilometers, it begins to remain on the converter cells. Also, signs of a clogged catalyst are the small diameter of the throughput cells. Due to the high concentration of resins and impurities in the fuel, they are easily clogged in this element.

Note that poor fuel quality plays an important role in the life of the catalyst. With frequent use, bad fuel settles in the exhaust manifold, not having time to completely burn out in the chamber. This can cause overheating of parts of the catalyst. Mechanical damage also plays an important role. The slightest hit on an unevenness (the same speed bump) will cause the element to deform, due to which it will not function normally. Small crumbs that have broken off in the catalyst cavity easily clog small honeycombs. Thus, the main signs of a clogged catalyst (VAZ-2172 is no exception) are associated with the inability of the system to “release” exhaust gases normally, due towhat they stagnate in the exhaust pipe and cylinders. This provokes a large loss of power and increased fuel consumption.

What to do if the catalytic converter is clogged? Do-it-yourself signs and diagnostics of an element

There are three ways to check it. The first is the most effective.

This is a test of the catalyst during its dismantling. It attaches very easily. For dismantling, you need to take two box or open-end wrenches for 13. On the one hand, we fix the bolt, and on the other, we turn the nut counterclockwise. However, difficulties may arise. Since the catalytic converter is located under the bottom (not the cleanest place in the car), its fasteners can simply rust.

And the standard WD 40 does not help here. Therefore, in half the cases, you have to pick up a grinder and cut off the bolts. But that's not all. Since the converter is part of the exhaust system, it works at elevated temperatures. Accordingly, its parts (one goes from the receiving pipe, the second - to the resonator) simply stick to the neighboring metal. In this case, only blows with a hammer save. But this is not the best solution. As we said earlier, from the slightest blows, the inside is easily deformed. Cutting the remaining elements with a grinder to remove the catalyst is also not an option. Therefore, it turns out that removing this element to the outside is not so simple. Well, if the catalyst has not stuck, with its successful dismantling, we carefully examine it for blockage - betweenmeshes should be a through clearance.

Second way

This diagnostic method is performed without mechanical intervention - the catalyst remains in its rightful place. The method involves measuring the pressure in the system. To do this, a pressure gauge is screwed into the place of the oxygen sensor (sometimes an adapter is required) and readings are measured at different engine speeds.

At 2.5 thousand, the normal level is 0.3 kgf/cm3. If the value is less than the permissible value, the gases are not able to exit normally. Because of this, the car loses power. Also, diagnostics can be done using a motor tester (the most technologically advanced method today). A pressure sensor is screwed into the cylinder in place of the candle. Then, at different crankshaft speeds, the waveform is analyzed. Naturally, all this requires equipment, so the first method is more familiar to our car owners.

Delete item

If your catalytic converter is clogged (we examined the symptoms of a malfunction), it must be replaced with a new one.

However, there is a problem - the average cost of new converters is about $100. Therefore, motorists simply remove it from the system by installing a flame arrester or a spacer in the form of an ordinary pipe in its place. However, after such actions, the catalyst is necessarily removed from the ECU unit (car brains). It is believed that this action will increase the power andmachine acceleration by 5 percent (due to better ventilation of exhaust gases).

So, we have looked at why the catalyst is clogged, the signs of a malfunction and how to solve it.