The exhaust gas muffler system of the car consists of a main and additional muffler, a catalytic converter of exhaust gases, an exhaust manifold and connecting pipes
All parts of the system, except the exhaust manifold, are welded into a single unit.
The exhaust system is attached to the body with rubber pads.
The exhaust manifold is secured with nuts to the cylinder head studs
A metal gasket is installed between the exhaust manifold and the cylinder head
The intake pipe is attached to the exhaust manifold flange with two studs with nuts
The flanges are tightened by two nuts and cylindrical springs put on the studs of the exhaust manifold
An O-ring with a spherical surface is inserted between the flanges
A control oxygen concentration sensor in the exhaust gases (lambda probe) is installed in the lower part of the exhaust manifold.
The second oxygen concentration sensor (diagnostic) is installed in the pipe after the catalytic converter.
The three-component catalytic converter is designed to reduce emissions of carbon monoxide, nitrogen oxides and unburned hydrocarbons into the atmosphere.
The catalytic converter is a ceramic block with many pores coated with afterburning catalysts: rhodium, palladium, platinum.
Passing through the pores, carbon monoxide turns into carbon dioxide, unburned hydrocarbons into water vapor, and nitrogen oxides are reduced to harmless nitrogen.
The degree of gas purification in a serviceable neutralizer reaches 98%.
For the normal operation of the neutralizer, the composition of the exhaust gases (in particular, the oxygen content in them) must be within strictly specified limits.
If lead compounds are present in the exhaust gases, the catalytic converter and the oxygen concentration sensor quickly fail.
Therefore, even short-term operation of a car on leaded gasoline is strictly prohibited.
Also, the cause of the failure of the neutralizer may be a faulty ignition system or power supply system.
If ignition is missed, unburned fuel, getting into the neutralizer, burns out and sinters a block with catalysts in it, which can lead to a blockage of the exhaust system and a stop (or a severe loss of power) of the engine.
Silencers and a catalytic converter connected by pipes are unassembled units, they must be replaced with new ones if they fail.
The spare parts are supplied with a neutralizer with a receiving pipe, additional and main silencers with pipes of a certain length, as well as special clamps for connecting pipes.
To replace a separate element of the whole system, in two places on its pipes there are marks (cores) on which pipes can be cut.
Maintenance of the exhaust system consists in its periodic inspection, checking for tightness of joints and the presence of through corrosion, provides for tightening of weakened joints and replacement of rubber suspension cushions.