Exhaust system VAZ 21099: device and design

Essential elements

The VAZ 21099 exhaust system diagram includes the following units:

exhaust manifold;
gas receiver;
main muffler;
additional muffler;
pipelines;
connecting and fastening elements;
elastic rings for hanging.

Exhaust gases pass from the exhaust port through the manifold. It is made of cast iron alloy and secured with a nut connection. Thanks to the high heat capacity of cast iron, it is possible to reduce the parameters of the temperature field in the engine compartment.

The exhaust manifold pipes fit into the gas inlet. This element allows you to implement the system according to a single-pipe scheme. This solution reduces the weight of the structure.

The noise suppressor is a thin-walled pipe of a special shape. Steel alloys are used as materials for the production of such parts.

Basic faults

In general, the muffler and the VAZ exhaust system itself are quite reliable. In fact, there is almost nothing to break there. Therefore, the worst thing that can happen to a driver is a broken muffler, and this happens very often on our roads.

Muffler VAZ 2109

Removal and repair of the main muffler

If, after encountering a deep hole, bump or pothole, the VAZ 2109 car begins to work much louder, most likely the main muffler has been broken and an additional hole has appeared in it. Russian automobile technical regulations prohibit driving with a faulty system, so you have no choice but to undertake muffler repair.

In general, there are 2 simplest options for fixing the problem: replace the old VAZ 2109 muffler with a new one or weld it. Of course, you shouldn’t do welding yourself – you need the appropriate skills.

However, in any case, you will have to remove the muffler for replacement or repair, so let's talk about how to do it correctly.

First of all, stock up on the necessary tools. To dismantle the muffler you will need:

The socket is 13. The deeper it is, the better.
The key, which many drivers call a ratchet, and also a socket on “13”.

The whole process, as you might guess, is carried out on a lift or on an inspection pit. It is very important to wait until the exhaust system and the main muffler have completely cooled down before starting any manipulations, otherwise everything will end in severe burns.

If everything is in order, proceed directly to dismantling the muffler:

We start by disconnecting the main muffler from the resonator. To do this, find a clamp. Grab the fastening nut with a spanner and, holding it from turning, use a ratchet to unscrew the bolt itself.
Once the bolt is removed, the clamp itself can be disconnected and removed to free the main muffler from the resonator.
Now carefully remove the front part of the muffler from the rubberized suspension. After doing the same, pull it out from the rear suspensions and the entire exhaust gas outlet device of the VAZ 2109 can be pulled out.

Now either change the main muffler or weld the holes. Installing it on a VAZ 2109 is done in the reverse order and, as a rule, does not cause any particular difficulties.

Replacing an additional muffler

Everything here is just as easy. The whole process can be divided into several stages:

In the same way, disconnect both mufflers, main and additional.
Now disconnect the device from the catalyst. Also, using a spanner, you need to unscrew the 2 mounting bolts.
Now you can slightly lift the unit and disconnect it from the rubber suspensions. If you can’t do this manually, you can pry off the pendants with a screwdriver.

At this point, the additional muffler can be removed even easier than the main one. Reinstalling the part is done in the reverse order.

Catalyst replacement

This device very rarely fails, however, the skills to repair and dismantle it may still be useful to you. An important tip before you start, keep in mind that during operation this part heats up to 600 degrees and cools down much longer than the main and additional mufflers.

The dismantling process itself is schematically as follows:

First of all, disconnect the catalyst from the additional muffler. Remember to hold the nuts with a spanner.
Next, in the same way, unscrew the bolts that secure the catalyst to the receiving pipe.
That's it, the catalyst can be carefully removed from the rubber lead and pulled out of the car.

In fact, as you already understand, repairing an exhaust pipe is a simple matter and can be easily done alone if you have all the necessary tools. The main thing is to follow safety precautions.

The exhaust system of carburetor engines of VAZ 2108, 2109, 21099 cars consists of three parts: a receiving pipe, an additional muffler and a main muffler.
The parts of the system are connected to each other by means of flared pipe ends and metal conical sealing rings located between them, clamped with clamps. The system elements are attached to the engine exhaust manifold with a flat flange on the exhaust pipe, through a gasket and four studs with nuts. Elements of the exhaust system of VAZ 2108, 2109, 21099 cars
The exhaust system is suspended from the body by brackets on rubber rings-cushions (5 pieces). In the front part, the exhaust pipe is additionally secured with a bracket from the engine.

The exhaust pipe of the exhaust gas exhaust system consists of two pipes attached on one side to a flange, on the other to a gas receiver consisting of two stamped metal halves. The gas receiver, on the side of the additional muffler, ends with a metal intake pipe flared at one end. The gasket between the exhaust pipe flange and the engine exhaust manifold flange is made of asbestos reinforced with perforated steel tape.

An additional muffler (resonator) consists of a housing with a perforated pipe and partitions inside. The additional muffler pipes also have flared edges for connection to the exhaust pipe and the main muffler. The outside of the optional muffler can be treated with aluminum to improve corrosion resistance.

The main muffler also consists of a housing with perforated pipes and partitions inside. The housing can be made of stainless steel to prevent corrosion. Two pipes are attached to the muffler body: on one side, flared, for connection with an additional muffler, on the other side, straight, for exhaust gases.

Both mufflers do not have welding points and are assembled by rolling parts to prevent corrosion.

Diagram of the exhaust system of a carburetor engine of VAZ 2108, 2109, 21099 cars

Notes and additions

— On VAZ 21081 cars, the muffler exhaust pipe is single, not double, since the exhaust manifold of the 21081 engine has one hole.

— The exhaust system of the injection engine of VAZ 2108, 2109, 21099 cars is discussed on our website in the article: “Exhaust system of the injection engine of VAZ 2108, 2109, 21099 cars.”

More articles on VAZ 2108, 2109, 21099 cars

— “Shoots” at the muffler, reasons

— “Shoots” at the carburetor, reasons

— White smoke from the muffler, causes

— Blue smoke from the muffler, causes

— Black smoke from the muffler, causes

VAZ-2109 owners are often interested in how the exhaust system of their car works. Curiosity in this case is far from idle. Some want to do repairs and want to know what and how it works here. Others thought about such an option as tuning, that is, modification, for example, installing a Stinger exhaust system. In any case, if you want to do this work yourself, you first need to familiarize yourself with the design features. Well, don’t forget about the main purpose of this system – to remove exhaust gases to the outside and reduce noise. Accordingly, incorrect intervention can lead to unpleasant consequences.

The difference between the new generation models

The emergence of new engines led to the need to redesign the car. Now the VAZ 21099 exhaust system with an injector began to include additional units. With their help, it was possible to reduce the amount of harmful emissions and improve engine performance parameters.

The exhaust system in this case additionally includes:

lambda probe (sometimes called an oxygen sensor);
catalyst.

The peculiarities of engines with an injector require constant monitoring of the quality of the supplied working mixture, as well as exhaust gases. Changing such proportions is carried out at the command of the electronic engine control unit. Therefore, the exhaust pipe of such cars is equipped with a lambda probe.

The conversion of carbon monoxide and nitrogen oxides is carried out using a catalyst. It is installed in front of the additional muffler (resonator). The body of this device is enclosed in a special shell to increase strength and compensate for thermal expansion.

Design Features

All domestic cars have approximately the same exhaust system. This greatly simplifies the issue of self-repair without the involvement of specialists.

The exhaust system (ES) includes several main components.

System element	Functions
Downpipe	A special probe is placed inside this pipe. This device studies the composition of exhaust gases, controls and analyzes the composition of the mixture that goes into the cylinder block
Catalyst	This is the very element of the system that allows you to minimize the harmfulness of gases escaping from the aircraft.
Additional muffler	It is mounted to the catalyst using a special clamp. The purpose of the additional muffler is to absorb the main noise, so the sound at the exit from the pipe is insignificant
Main muffler	The same component that peeks out from under the rear bumper of your car. It connects to the additional muffler with a clamp

Main components and fasteners

The entire exhaust system of the VAZ 2109 car is in a suspended state and is held in place by the presence of rubber mounting hangers. The hangers, in turn, are screwed to the bottom of the car.

Popular faults

The exhaust system itself, together with the muffler, is quite reliable and durable due to its simple design.

Frankly speaking, there is nothing to break if you compare the aircraft with the engine, fuel, oil system, and so on.

The most common and unpleasant situation that can happen to an aircraft on a VAZ 2109 is a broken muffler. This is due to the quality of our roads, or rather to their absence.

Features of operation

The exhaust system of the VAZ 21099 with a carburetor or injection engine is quite simple and reliable. However, owners of these models should take into account some operating features.

The low location of the system parts leads to mechanical and corrosion damage to the parts. When performing periodic inspections, you should pay attention to the condition of the elastic suspensions and connecting elements.

All damaged parts should be replaced as soon as possible, since the aggressive environment of exhaust gases provokes the rapid development of corrosion damage.

All work on the exhaust system should be performed in well-ventilated areas or outdoors. The threads on the nuts and studs of the exhaust manifold are often deformed due to constant temperature changes. As a result, dismantling such connections can cause additional difficulties.

Particular care is required when working with the catalyst. The temperature on the surface of the housing often reaches 500-6000C, so work in this area should begin after the parts have completely cooled.

How to determine whether a muffler is faulty

You can identify problems with the muffler yourself, without having any special knowledge of the automotive industry. First of all, while driving, occasionally monitor the composition of the exhaust gases. If black smoke comes out of the pipe when you press the gas pedal, then the mechanism is probably burnt and has holes.

Experienced car enthusiasts know that it is better not to bring the condition of their “glushak” to a critical level, but to identify the smallest faults in advance:

Check if there are knocking or gurgling noises in the exhaust pipe while driving.
Raise the car on a jack and inspect the exhaust pipe. All parts must be free of rust, burns or holes.
Observe whether moisture drips from the muffler pipe connections. The accumulation of condensate will quickly lead to the formation of rust and corrosion of the metal.
Assess how hot the engine gets after short trips. If the engine seriously overheats, this may be the first signal that the exhaust system is not working correctly.

If the muffler knocks

Most often, car enthusiasts complain that the device begins to knock loudly while driving. In this case, the pipe can be struck either against the body of the gas tank or against the body of the car.

The knocks can be very loud, which leads not only to a decrease in ride comfort, but also to rapid deformation of the muffler itself. In these cases, it is necessary to immediately take measures to isolate the pipe from the tank or body:

change the hanging rubber bands (it is quite possible that during operation they have become very stretched and can no longer hold the pipe in one place);
if the knocking starts after replacing the device, then you need to turn the mounting flange and make sure that all the gaskets are in place exactly;
if the muffler was replaced with a “cooperative” one, homemade or from another car model, then you need to try to ensure that all fastening connections and joints exactly match the original.

If the pipe swings strongly, it is necessary to replace the rubber bands with new ones.

If none of these measures gives results, you will have to cover the impact area of the muffler with a thick piece of rubber. Rubber will eliminate the sound of impacts and protect the surface of the pipe from deformation.

What to do if the muffler is broken

You can break through the device very simply - just drive at high speed on an uneven road. Even the thickened walls of the pipe cannot prevent the metal from being severely deformed, and holes may even form.

The legislation of the Russian Federation clearly indicates that operating a vehicle with a broken muffler is prohibited.

If the driver discovers that the mechanism is broken, he has only two options:

Replace with a new one. This is the easiest way, besides, you can buy a home-made “glushak” and install it on the car yourself.
Using a welding machine, weld a hole in the housing. This option is more expensive, since it is necessary to apply welds very carefully so as not to burn through the muffler. In addition, the driver does not always have the skills to operate the device and has to turn to specialists.

Operation of a muffler with a hole is prohibited