The car’s exhaust system is a complex system. Responsible for the evacuation of flue gases, with any fault it gives the owner clear signals that something is wrong. A metallic noise or too loud operation of the car are obvious signs of failure. In addition, if you focus on the main element, and thus the exhaust pipe, you may have to deal with various types of defects. Unsealing the system at the junction with a muffler or catalyst usually requires the intervention of a mechanic. Our actions, whatever they may be, can only harm. However, in the case of a hole in the pipe, there is a chance that we will avert the problem ourselves. Appropriate exhaust system repair elements are sufficient. A specific exhaust first aid kit.
When does a hole form in the exhaust pipe?
It really doesn’t matter how long you drive a car. Such a malfunction can occur in both the new model and the venerable one. What causes this?
First, corrosion, which usually arises for reasons beyond our control. Here, mainly unfavourable weather conditions are blamed, in particular, those prevailing in winter. Roads sprinkled with salt in combination with snow and water create ideal conditions for the development of unwanted red coating.
Sometimes we are also guilty of rusting important parts of the car. It’s about standard negligence like rarely washing a vehicle. We do not flush regularly accumulated salt. And if we wash the car, then we do not think about using anti-corrosive preparations. We also often disregard the first signs of rust. And this is a simple way for the phenomenon to spread at an alarming rate.
In addition, all kinds of cracks are equally dangerous for the exhaust pipe. They are usually the result of too reckless driving, hooking curbs or driving on unpaved roads.
Assuming, of course, that the fault is only a hole on the surface of the pipe, it is worth trying to solve this problem yourself. How? Of course, using special products. Exhaust system repair elements include, among others, bandages and silencer repair tapes, cement and patches. Also, don’t forget about clamps, entire pipe connectors or flexible connectors in case the damage is large.
Exhaust system repair elements – what do we need for self-repair?
Bandages and tapes are products with a fairly low price. They are easy to use, so it’s definitely worth equipping yourself with them. They are especially useful when travelling. If something happens to our exhaust system on the road, the most important thing is the speed of reaction.
However, it should be remembered that this type of solution is temporary. Fast, efficient, but only for a while. Such products are mostly made of aluminium, which is why they are characterized by exceptional resistance to adverse weather conditions. Their operation is not disturbed by high temperature, which is the result of the pipe heating up during the car’s operation. In addition, in the bandage set, we usually also buy a cable band, which greatly facilitates the whole process. Repair goes faster and easier. In fact, it is enough to wrap the damaged area very tightly, and then secure it with a band.
Exhaust system repair elements – cement and patches
Other exhaust system repair elements are, of course, cement and so-called patches. Special cement enables sealing of cracks or cavities. If we notice that a hole has formed in the exhaust pipe, it is enough to apply a layer of cement on it, and then distribute it thoroughly. However, with this method, it happens that once is not enough, and we have to repeat the action. In turn, patches work like bandages. In fact, it is enough to stick them on the defect to temporarily stave off the problem.
Temporary exhaust system repair elements are one thing. On our own, we can also try to remove rusty elements and replace them with new ones. However, we should not take this action while travelling. It often turns out to be impossible. When removing parts that have been attacked by corrosion, you must have a welder to keep the system tight. The whole procedure consists of removing old, rusted parts and welding new ones in their place. If we approach the matter really solidly, the repair effect can serve us for many years.
How do I know if I can do it myself?
Either way, regardless of which method we choose and which repair components for the exhaust system we use – the preparation must be the same. We should remember to thoroughly clean the repaired area beforehand. We can use a stiff, wire brush or sandpaper for this purpose. It’s about something that will thoroughly remove rust. If the defect is not properly cleaned, it is very likely that any patching attempt will fail.
When we already know how to fix a possible hole, the question remains: how do you even realize that this is the problem? The correct diagnosis is sometimes a difficult task. We will not always be able to see the defect with the naked eye. Listening from where exactly unpleasant sounds can be heard is also of little use.
To properly and correctly assess the problem, we must first wait several dozen minutes from the engine alone. So that the exhaust can cool sufficiently. If we take action too soon, we can get burned. To see the car from below, of course, we can slip under it, but a much better option is the channel or ramp. In the absence of such opportunities, let’s try, at least to raise the car. His height should allow us to lie down freely.
Once you’re directly under the car, let’s carefully study the entire exhaust system. Let’s look for a hole that can eventually turn out to be a source of problems and noise. When undertaking any repair, however, remember that it is pointless to deal with heavily damaged components. An equally bad idea is to try to fix the fault in an element that is already covered in rust in many places. Most likely, the situation looks even worse inside. Repair makes no sense then. We must understand that the exhaust system will wear naturally and all parts will need to be replaced over time.
Exhaust system repair elements are not everything. How to care for the exhaust system?
To extend the life of individual components of the exhaust system and not to lead to the need for their replacement or repair too quickly, it is worth taking care of the system.
First of all, it is good when we properly secure the car. What does it mean? Among other things, the fact that we remove salt residues from it in the winter, and paint the outer coating with special paint. Regular suspension control is also important. What’s more, during your visit to the mechanic, you can ask him to additionally secure the muffler. He will do this with the help of fasteners, brackets or so-called hangers.
For the catalyst, there are several methods for extending its service life. It’s all about avoiding puddles. While driving, the car engine gets very hot. Its rapid and sudden cooling can quickly damage individual components, including the catalyst. Secondly, whenever possible, it is preferable to avoid short distances and winter driving. The engine is not able to warm up properly during them. And this, in turn, leads to the accumulation of unburned fuel residues. And finally, thirdly – all potholes on the road should be overcome with a great deal of caution. The catalyst is very delicate. The muffler itself can also quickly break down during heavy driving.
Faults other than just a hole in the exhaust pipe. What are the most common damages in the exhaust system?
Finally, it is worth looking at the most common exhaust system faults. The hole discussed in the article will not always be a problem. If we are not able to determine for ourselves what exactly is happening with the car – it is necessary to visit a mechanic. However, there are some symptoms that can give us something for thought.
When we hear a loud noise, we may assume that the muffler is damaged or a hole has formed in the exhaust system. For unknown reasons we feel gas in the car, most likely it is a system leak. When we get the impression that the engine is choking, we are most likely dealing with a clogged catalyst or DPF. In a situation where the engine begins to stall, and we have a problem with its restart, it means that the recirculation system fails.
Other causes of trouble with the exhaust system are also rust, i.e. corrosion and clogged particle filter, for which indicator points. As you can see, there can be a whole lot of causes and faults. We are able to deal with some of our own, but not necessarily with others. The fact is, however, that eventually, the day will come when the item will have to be bought again.
The car’s exhaust system is one of its most important elements. In each car model, it is responsible for a number of extremely important functions. Functions without which the machine cannot works properly. These include noise reduction, flue gas cleaning, removal of combustion by-products or minimizing heat radiation as much as possible. The exhaust system includes a catalyst, flexible connector, pipes, probe and silencer. And although each of these elements is responsible for something else, the said connector and pipe connector are very often mistaken.
In order to understand the differences between these two elements, one needs to consider their characteristics and the main tasks they perform. The fact that both parts suppress unpleasant vibrations is obvious. But above all, they differ in construction. Let’s start with the flexible connector – its function, replacement process and accurate measurement.
Flexible connector – what is it and what does in the car?
It is obvious that the operation of an internal combustion engine causes specific vibrations. It is the design of rotary piston engines that forces such a reaction. However, these vibrations necessarily transfer to all other engine-related components, including the exhaust system. And unfortunately, this is not only undesirable but also harmful. It does not affect the whole structure very well. In addition, the noise level is then louder.
And precisely to minimize this process, and thus reduce the level of vibration – so-called flexible connector is used. In other words, a compensator or intermediate element of the exhaust system, i.e. an element made not of a solid pipe, but of a characteristic steel braid. With its help, it is possible to virtually eliminate unwanted vibrations, and more specifically transfer them to further elements of the system. These include exhaust pipes and silencers. What’s more, the connector also protects the collector from cracking.
Which cars require a flexible connector? In fact, all that have internal combustion engines. These include standard motor vehicles, agricultural machinery and construction machinery – harvesters, excavators and loaders. In addition, a connector is also required for internal transport devices, for example, forklifts. As if that was not enough, it is also used in vessels and mining.
When should the flexible connector be replaced?
If the exhaust system requires a flexible connector to be replaced, we will hear it immediately. The car starts to work very loudly, especially at higher speeds. We also hear a characteristic knock under the chassis. This reduces driving comfort and negatively affects the entire car. When the vibrations cease to be damped properly, the engine transfers its energy to other elements of the exhaust system, e.g. exhaust pipe or hangers. A catalyst that is not adapted to such conditions feels it the most.
When does this happen? For example, when we hit something with a car chassis. Another reason may also be a bad fit of the connector or improper mounting of the element. It is also normal for the braid to be damaged by natural exploitation. Unfortunately, it cannot be repaired. In the event of its wear, we must buy a new replacement.
We have a choice of both bi-directional and unidirectional standard connectors. What is the difference? The first will serve us regardless of the direction in which we will mount them. In turn, the second, because of their properties must be assumed in a specific way. Which flexible connector we choose depends on us.
How to properly choose a flexible connector for our car? Accurate measurement is needed before purchase.
Before we decide to buy a flexible connector, we need to know if it will perfectly match our car. To do this, you must first measure the used item. Preferably, when this is still under the car.
The conviction that measuring is not required because there are catalogues that clearly present all information – it can be fatal. Most often we will not find the exact dimensions of the model there. So if we have to make a measurement, how do we go about it?
Two things should be of particular interest to us. There is the diameter of the pipe just before or after the joint and its total length. How to do it without being able to use the under-car pit? It’s quite simple. Just slip under the car and with a simple measure or ruler or measuring tape, and gauge exactly the distance from the weld to the weld. Then proceed to measure the diameter of the pipe. It’s best to do this with a calliper, but if someone does not have it – maybe just a gauge circumference, then divide it by 3.
Pipe connector – what is it responsible for and what are its functions in the car’s exhaust system?
The so-called pipe connector is, as the flexible connector – an element mounted in the exhaust system. Its main task is to create a tight, hermetic connection between successive elements of the exhaust system. This attachment reduces the vibrations that are transmitted to the body. However, it is usually much shorter and stiff. Often it is sold immediately with two clamps.
Due to the fact that the element does not have a predetermined service life, it is considered to be suitable for replacement when it simply wears out. This should not be postponed because loosening the mountings may result in defects in other parts of the car.
And how do you know that the pipe connector is already defective? Just take a look at him. As it is exposed to moisture, it becomes covered with a white coating over time. What’s more, as a result of corrosion brown spots and marks appear on it. On the other hand, under the influence of temperature changes, the characteristic fastenings lose in the element. When this happens, we will certainly hear it. You can hear specific, unpleasant noises from the chassis.
Never underestimate the loud operation of the car!
Due to the fact that the exhaust system is a fairly advanced system, any malfunctions associated with it can be quite dangerous. And given the fact that its individual components wear out over time, you should be vigilant. You also have to accept that damage to specific parts is inevitable. Although, depending on their quality, we are talking here about a different time period. The way the car is used is also important. More often, the defects of the exhaust system apply to cars that travel a lot on urban roads.
Either way, as has already been mentioned, suspicious sounds are a sign of trouble with the exhaust system. These can be heard when the muffler or exhaust pipe starts to fail. The car becomes loud, and sometimes you can also smell the gasoline. If the muffler is burned out, its defect directly translates into the operation of the entire engine. This one begins to “choke”. The exhaust gases return to the chamber and the gasoline-burning process is disturbed.
To some extent, it should be comforting that usually, only one element of the entire exhaust system fails. The risk that the exhaust system will be destroyed in its entirety is really negligible. However, if you detect any uncomfortable symptoms yourself or with the help of a qualified specialist – react. In the event of a fault, it is almost always necessary to repair or completely replace the worn part. It is better to replace one pipe connector or flexible joint than to cause a more expensive catalyst or muffler to fail.
Fortunately, a new flexible connector or pipe connector is a low cost. A small element, although seemingly trivial, is of great importance. Thanks to it, we are able to stop unpleasant vibrations and noises.
The middle muffler is a very important element of the car’s exhaust system. Unfortunately, this is also one of the most vulnerable parts. This is due to the fact that it is located in the chassis (making it easy to find various types of mechanical defects). The second reason is the working environment.
Meanwhile, the middle muffler affects not only the work of the exhaust system but also the functioning of the entire car. Driving comfort, fuel consumption and engine operation depend to a large extent on its efficiency and reliability.
Do You want to minimize the risk of damage, including primarily the defects in the middle muffler? it is worth knowing the specifics of the exhaust system and remembering a few important rules during its operation.
Middle silencer as part of the exhaust system
In addition to the middle silencer, the car’s exhaust system consists of several other elements. It includes the following parts:
- exhaust manifold with an exhaust pipe;
- front silencer;
- middle silencer;
- end silencer;
- exhaust pipe.
The smooth and harmonious functioning of all these elements guarantees comfortable and safe driving.
What functions does the middle muffler perform?
The middle silencer, like the final silencer, is responsible for suppressing the sound of the engine. The second task is cleaning the exhaust gases released into the atmosphere. It is a particularly important element also because it reduces the vibrations of the high-frequency system. It also protects the exhaust system from falling into resonance when it is at high speed.
A damaged middle silencer can seriously affect drivers, so care should be taken to ensure that it functions properly. This is often a very difficult task. Due to its location in the car, it is often exposed to malfunctions or adverse external factors.
The exhaust system in danger. What hurts it?
The exhaust system is located in the chassis. It is, therefore, more vulnerable to damage and adverse external factors, including those associated with the weather. What harms it the most is excessive moisture, road salt (in the autumn and winter season), but also mechanical damage caused, for example, when driving on uneven surfaces.
Proper maintenance and care of the components are therefore crucial to minimize the risk of damage and to maintain the efficiency and proper functioning of the exhaust system as long as possible. It is also worth being vigilant to catch any irregularities in good time. Driving a vehicle with damaged parts can have serious consequences, for example, destruction of the catalyst.
How do you know if the middle muffler is damaged?
Every driver knows his car as his own pocket. This is why he can usually judge correctly when not everything is working properly. Observation of your own vehicle is extremely important, according to the principle that prevention is better than cure. It also applies to all motor vehicles.
It’s worth watching your car and reacting if you notice something disturbing. For the exhaust system and the damages of the middle muffler, the symptoms may be as follows:
- the odour of exhaust gases in the car cabin – its reason may be incorrect ending of the exhaust system components;
- noise – caused just by a damaged middle muffler;
- breaking or tearing one of the elements of the system – for example as a result of corrosion, improper assembly or obstacle on the road;
- catalyst damage – caused by clogged mufflers or increased emissions to the environment.
A damaged middle silencer can lead to even greater damage and malfunctions in the entire exhaust system and even the vehicle itself. What can you do to defend against this and prevent malfunctions?
Exhaust system service and maintenance
Specialists advise making special efforts to ensure proper maintenance of all components of the exhaust system. This is so important primarily due to the fact that it contains a lot of parts that can easily be subject to corrosion or faster wear.
Regularly check and replace parts that show signs of any damage as they are highly prone to corrosion. Neglecting this fact can lead to much more serious problems.
Mechanics suggest that parts be inspected and replaced every 18 months or when we notice any irregularities. Otherwise, replacing the entire system can be much more expensive. Moreover, using a car in which the middle silencer or other exhaust system component is not working properly can lead to more serious damage, for example to the destruction of the catalyst.
An efficient car is a perfectly working exhaust system
A lot depends on the proper functioning of the exhaust system, including all its components, such as the middle muffler. Examples include driving comfort and a functioning engine. To maximize its service life, it should be taken care of by regular inspections, as well as using anti-corrosive coatings.
The exhaust system is one of the important elements of the car, although at first glance it does not seem. In fact, it is responsible for several important functions that a car cannot do without. That is why you need to take care of it properly so as not to damage it. How to take care of the car’s exhaust system? Here are some tips.
Construction and functions of the car exhaust system
How to take care of the car’s exhaust system? Before we get to that, we need to explain its essence. The exhaust consists of a catalyst, silencers, lambda probe, connecting pipes and flexible connectors.
Each of these elements is responsible for something different. The exhaust collector collects the gases formed as a result of combustion and then delivers them to the catalyst, whose task is to reduce harmful chemical compounds. A silencer, as the name suggests, suppresses engine noise, and the lambda probe collects information about exhaust gas levels. The functions of the exhaust system include:
- removal of by-products of the combustion process,
- flue gas evacuation,
- noise reduction,
- exhaust gas purification,
- minimizing exhaust heat radiation.
How to take care of the car exhaust system?
That’s why you need to be able to protect yourself well. Rust is formed as a result of poor working conditions – It is enough to remove road salt residues after winter, protect it with special high-temperature paints or control the suspension of the vehicle.
As the corrosion progresses, it causes mechanical damage – which can lead to clogging of the exhaust pipe. Consequently, the car’s engine chokes and its power drops.
When visiting a mechanic, you can ask him for additional protection against excessive vibration. Special elements are then used, e.g. supports, brackets or hangers.
The catalyst is the main element of the exhaust system. However, like all things, its life finally ends. In this case, a new one or spare parts should be installed. There are several tips that can effectively extend his life.
The first of them talk about not going into deep puddles at high speed. The engine is warmed up while driving, its rapid cooling can seriously damage individual components, especially the catalyst and exhaust manifold, which are closest to the engine and have the highest temperature.
Secondly, avoid short distances, mainly in winter. The car’s engine will not be able to warm up well then. This results in the accumulation of unburned fuel residues. This causes corrosion of the metal elements and that the remaining fuel burns in the catalyst.
Thirdly, you should carefully overcome any road unevenness, including slowdowns. One should know that the catalyst is quite delicate, especially due to the contribution, which can be ceramic. Therefore, any mechanical damage is very often the cause of its malfunction. The car’s silencer can also be interrupted during a quick collision with a hump.
Why is car exhaust system important?
It is worth taking care of the exhaust system, not only to save money that would be spent on repair. An efficient system does not cause combustion problems. This is important for ecological reasons.
In addition, a dysfunctional exhaust system can translate into poor engine performance, damaging it. It all affects the functioning of the entire car, and therefore, its trouble-free use. It is also worth saying that you cannot move a vehicle whose exhaust system is damaged. Such driving threatens the imposition of a mandate by the police or even the retention of a registration certificate.
Exhaust system malfunctions – possible diagnoses
Finally, we can say about the damage that may occur in the system. They are guidelines that may not be the real causes of the fault. Therefore, any irregularity should be carefully checked with a car mechanic. This will allow you to pre-diagnose the cause of the problem, and thanks to the faster response it will not cause much damage to the car.
- loud noise – the muffler is damaged or corrosion has caused a hole in the exhaust system,
- damaged hangers that caused tearing of the exhaust system – as a result of corrosion or while driving, damage occurred, e.g. by collision with something on the road,
- the feeling of exhaust gases inside the car – system leakage, hole in the system caused by rust,
- “check engine” and emergency mode – the lambda probe is not working properly or has failed, the catalyst is clogged,
- high fuel consumption with a decrease in power – lambda probe failure,
- power drop, and at the same time stifling the engine – clogged catalyst or DPF filter,
- the engine goes out, there are problems with its starting, the “check engine” indicator lights up, the smell of exhaust gases in the coolant – the EGR exhaust gas recirculation system does not work properly,
- various types of visible places covered with rust – insufficient protection of the system by the manufacturer or improper maintenance. Very often it attacks exhaust pipes. You have to pay attention to such things because only a fully functional exhaust system does not increase the emission of harmful substances,
- DPF indicator light on, power drop – DPF or FAP particulate filter clogged, mechanical filter damage, filter sensor damage, no catalytic fluid in the filter,
- the appearance of “check engine” and a decrease in engine power – SCR system failure, no AdBlue fluid in the tank, damage to the AdBlue injector.
What is the voltage oxygen sensor in the exhaust gas? A little technical approach to the topic will not hurt anyone. The more that sometimes you will have to face certain deadlines, even when repairing a car. The information contained in the article below will certainly help a little. Without a doubt, it is worth learning a few words about the voltage oxygen sensor. Be aware that it exists at all.
Sensor and equilibrium oxygen in exhaust gases
Oxygen, which is in a mixture of fuel and air, is used in the combustion process. At this time, the nitrogen-oxygen binding process also occurs. These two components of air do not react with each other until the limit of 1800 degrees Celsius is exceeded. In the combustion chamber, due to pressure and temperature higher than 1800 degrees, there is a reaction between nitrogen and oxygen. Which, as a consequence, produces nitrogen oxides. They reduce the amount of oxygen that is important in the combustion process. In addition, the exhaust gases leaving the chamber contain free oxygen, which is the result of:
unused oxygen in the combustion process (a result of the poor composition of the mixture, too short time or inappropriate conditions for such a process),
- unnecessary oxygen in the process of fuel combustion (when lean fuel).
Restoring thermodynamic balance
Determining the exact composition of the mixture burned based on the amount of oxygen in the exhaust gas is possible after examining the amount of equilibrium oxygen. Each oxygen sensor does this by restoring the thermodynamic balance between individual exhaust components. It then comes into contact with the catalytic layer that is part of the sensor measuring element. During such a restoration of thermodynamic balance, the following occurs:
reduction of nitrogen oxides decomposition into the original nitrogen and oxygen version,
restored oxygen from oxides and free oxygen from flue gases oxidize carbon monoxide and unburned hydrocarbons. Then carbon dioxide and water vapour are formed.
Such reactions cause the oxygen sensor to measure the amount of equilibrium oxygen released from the exhaust gas. Do not be surprised. However, it will be different oxygen than that measured in the exhaust gas analysers, which take into account only free oxygen.
What is a voltage oxygen sensor – construction
It must be said that a voltage oxygen sensor is the most commonly used type of sensor that determines the level of oxygen in the exhaust gas. From the outside, the exhaust stream flowing through the exhaust system catches the measuring element. In turn, inside there is a sensor filled with atmospheric air, which is colloquially called reference air. This oxygen content in the air is constant and does not change.
The main and very important part of the voltage oxygen sensor is the so-called special ceramics. It consists of a solid electrolyte made of zirconia, stabilized with yttrium oxide. Both sides, inner and outer, are covered with thin layers of platinum. It has a special porous structure that lets gas through. It should be added here that the inner layer is a positive electrode and the outer layer is a negative electrode. Porous protective ceramics preserve the outer electrode and special ceramics that are exposed to contact with combustion residues.
The operating temperature of a voltage oxygen sensor is usually from 350 degrees Celsius to even 850 degrees Celsius. New oxygen sensors work at lower temperatures, from 220 degrees Celsius to 250 degrees Celsius. The measurement is possible due to the restoration of thermodynamic balance between exhaust gas components, in contact with the negative electrode. As a result, equilibrium oxygen appears from the exhaust gas. The amount of which can be measured by comparison with constant oxygen content in the reference air.
Voltage oxygen sensor signal
The oxygen sensor signal is the voltage between the external and internal electrodes measured with a voltmeter. This value depends on the amount of equilibrium oxygen. The value of the signal voltage depends on the composition of the burned mixture. Occurs when the exhaust gases affect the measuring element, and additionally, they are from the combustion of the stoichiometric mixture.
The average reference voltage is 450mV. The oxygen sensor driver program interprets the reference voltage value. When the signal voltage is greater than the reference value, then there is an interpretation that says that the exhaust gas covering the sensor is the result of burning a rich mixture.
However, when the signal value is lower than the reference voltage value, then the exhaust gases come from lean combustion. The voltage oxygen sensor controller will only receive information if the mixture is rich or lean. He will not receive any other information, even on the composition of the burnt mixture.
What a catalytic converter is and what it does in a car, almost every car owner knows. However, there is some popularly repeated information about it that is not entirely true. As in almost everything, some people’s opinions must be treated with a wink. Even more so when it is their opinions or information come from an uncertain source. The catalyst in the car facts and myths – it’s worth to know them.
The catalyst in the car – facts and myths
Speaking about its assumptions and main functions, it should first be clarified who invented the catalyst in gasoline engines. Very often the information that can be found on this subject is that in 1989 Opel came up with such an idea. Unfortunately, this is not true, and the Opel brand itself simply claims the credit.
In fact, American scientists working in the 1960s and 1970s are responsible for this. It all began with the technological development that flourished after the Second World War. The American and European market is affected by the mass of cars that are becoming commonplace. Such an increase was increasingly felt by the environment.
Research has shown more and more harmful substances in the air, so they began to develop ways to reduce them in exhaust gases. California was one of the first states in the US to introduce regulations that oblige manufacturers and users to have a catalyst in a car.
In the beginning – the myths
The catalyst is a container for impurities
It is a mistake that the catalyst is considered a container for storing unnecessary combustion products. Depending on the catalyst, it has a ceramic or metal insert. There are important elements such as rhodium, platinum or palladium, which react chemically with oxides emitted from exhaust gases. As a result, they are oxidized, and therefore the exhaust gases are cleaned. In diesel engines, the catalyst oxidizes hydrocarbon and carbon dioxide, and then, for example, the DPF filter takes over the role of purification.
Can LPG “kill” the catalyst?
Of course not! Another myth to refute. Gas installation, e.g. sequential, which is very well regulated and tidy, does not affect the catalyst in any way. Catalyst damage can occur when the installation is poorly assembled or the flat is too poor. However, it should be said that such situations occur everywhere.
The catalyst blocks exhaust gases and reduces the car’s performance
Will the horsepower in the car increase thanks to the cut-out catalyst? Myth. It was created in the 1980s when older cars had catalysts that to some extent paved the way of exhaust gases. If the car has one lambda probe in front of the catalyst, it is possible that its cut out will result in a smoother passage of exhaust gases. However, this applies only to older models. In the event that the system may have more probes after the catalyst, the only thing you get is the information “check engine”.
The last myth worth mentioning is that you can’t remove the catalyst in the OBD II diagnostic system. This assumption is that this system has two lambda probes, so do not cut the catalyst. This is a wrong assumption, if only because the OBD I system may also have two lambda probes. Therefore, it is not worth following it and blindly assume that a car with OBD I system does not have two probes.
Now it’s time for the facts
If the catalyst has a ceramic insert, it may be damaged after long driving or hitting a deep puddle. This is not a common situation, but it has to be honest that it can happen.
Another fact about the catalyst is that its clogging can stop the engine. If the ceramic insert breaks down and the system becomes clogged, the car will not start. While in gasoline engines with slow suction, even a half-clogged catalyst does not show this by power drops, engines equipped with turbocharging react differently. Even a slight clogging will affect the visible loss of horsepower. This is an important symptom. An unnoticed fault for a long time can affect the overall condition of the engine.
Catalyst and ignition system
It is also true that the catalyst may be damaged by neglecting the ignition system. The contribution is quite delicate, therefore all self-ignition and traditional exhaust pipe shooting do not work well on the life of the catalyst. During the bad work of the computer, which has bad fuel and air doses, the catalyst can be seriously damaged. Similarly, it applies to start a car “on a push”.
What to do if the catalyst is damaged?
Once you know that the catalyst has broken down, you have several options to choose from.
1. cutting it out of the exhaust system, welding it, and then inserting a spotlight or can in its place
2. buying a catalyst from the secondary market
3. buying a universal catalyst, dedicated to the given power and a given version of the engine
4. purchase of a replacement dedicated to a given model
The first two options are illegal, harmful or highly risky. A catalyst used is not guaranteed, you are not sure what is inside and how it is handled. The next two options are cheaper than the original parts from an authorized service centre.
It is assumed that the most complicated system in a car is the engine and electronics. You can not disagree that modern cars in no way resemble those of years ago, and the amount of automation is amazing. However, the exhaust system has always been underestimated. What’s more, it is the most often perishable system because it works in extreme conditions. The most common muffler problems, which occupies a leading place among spare parts, are the result of mechanical (curbs, stone and gravel chips), physical (wide range of temperatures from very high inside to low outside) and chemical (rust, road salt).
Nothing is forever, but it requires prompt diagnosis
Each part of the car has a factory-specified optimal wear time given in months or thousands of kilometers traveled. The average life of exhaust components is:
muffler – an average of 2 to 6 years, brand new up to 10 years
catalyst – an average of 50-100 thousand km, brand new up to 200-300 thousand km
DPF filter – on average 120-250 thousand km
exhaust manifold – ??
lambda probe – an average of 50-160 thousand. km
Usually only one part breaks. However, ignoring the defect for too long can affect other parts of the exhaust system. That is why it is best to go to the car workshop as soon as possible.
The main tasks of the muffler
The basic tasks of the muffler are:
ensuring optimal engine operation
flue gas evacuation
- noise reduction
- gas reduction
Each car produces, among others, carbon monoxide while driving. It is flammable and explosive when combined with air. If it gathered under in the car, it would be too dangerous for users also due to poisoning. The muffler pushes carbon monoxide and other gases under the vehicle, ensuring safety and clean air in the cabin. This key part of the exhaust system is also responsible for the pressure control necessary for the proper operation of the engine.
Depending on the model, there are two or three silencers connected in series – front, middle and end rear. The first (from after the engine) is an absorption silencer with low exhaust gas flow resistance. Mutes high sound frequencies because the tube is hidden in a can filled with sound-absorbing steel or glass wool. The second order one is the chamber silencer, which is responsible for reducing low sounds. Otherwise, it is called reflective and in turn has high resistance to exhaust gas flow. It is built of a number of chambers of various sizes that connect the pipes.
The noise coming from the engine, along with the vibrations, is significant. The muffler allows quiet and pleasant driving. It is responsible for the comfort of the driver, passengers and the environment. At the same time, the tremor does not translate is not transferred into a body.
The most common muffler problems – damaged muffler symptoms
When a leak appears in the muffler, exhaust gases will not only appear outside the exhaust system, but in worse cases also in the cabin. They are sucked in by the air from under the car. The first symptom is a suffocating smell, in more drastic cases also smoke. The noise level may also increase depending on which damper muffler has been damaged. However the noise, it will not be as big as at a hole in the exhaust pipe.
A less obvious symptom is the mechanical tearing or denting of the muffler or smaller elements such as hangers, seals, clamps or fixing bands. What every driver will definitely feel is a significant drop in engine power, throttling while driving, acceleration problems and low maximum speed. At the same time, combustion will increase quite significantly. This is due to some of the exhaust gas receding into the combustion chamber and an inefficient process. It may also indicate that the absorption silencer is clogged with cotton wool, which enters the main pipe through perforations.
The most common muffler problems – self-diagnosis
The easiest way to locate a leak is to clog the exhaust pipe with a towel to a depth of about 10-15 cm. If the sound does not change, it indicates a hole. Going from the exhaust pipe, we are looking for a place where exhaust fumes are emitted or smoked. We can plug it with a rag, then we should get a different sound and a larger amount of exhaust gas coming out of the outlet. However, there may be more leaks, so it’s better to find them all.
The most common muffler problems concern the end muffler, where the steam condenses, so faster corrosion occurs. However, the location of the entire exhaust system in the chassis causes its faster wear off. Road salt and moisture also attack fasteners. Therefore, pay attention to the ends and connecting pipes.
If the muffler it is clogged, check the temperature of the parts. The cold one is probably clogged. However, be careful because the gases after leaving the engine are around 800 degrees C, and at the outlet about 200-300 degrees C.
In the first article, we described what diagnostic trouble codes (DTCs) are and how they work. We gave practical examples of how to use them to diagnose the exhaust system. Here we will present the most popular examples of DPF error codes related to other failures. In the second part, you can familiarize yourself with error codes related to sensor faults.
P242F – DPF limitation – ash accumulation
Ash in the DPF filter is a product of the use of lubricating additives for engine or diesel oils as well as impurities resulting e.g. from corrosion or general engine wear. It settles in the DPF filter on the walls or in its back, and thus blocks its capacity. The soot can be burned off in the process of automatic regeneration. On the other hand, the ash can only be removed by washing or replacing the DPF.
The P2424F code will be issued in one of the cases:
- actual clogging of the DPF filter – be it ash or unburned other sediments, which in turn indicate ineffective self-regeneration
- the use of engine or diesel oil not adapted to the exhaust system with a DPF filter
- damage to the sensor or its circuits due to their opening or short circuit, breaking of the sensor cables
In addition to the P242F code, the board indicator light (MIL) may also come on.
P2463 – DPF limitation – soot accumulation
Ash is not the only product of combustion. The DPF also accumulates soot, which, fortunately, can be burned during self-regeneration. Its frequency is regulated by a pressure sensor that compares the outlet values with those programmed by the manufacturer. Excessive soot that has not been burned regularly can result in sending code P2463. It may also indicate a malfunction of the regeneration process, a damaged sensor or its wiring.
There may also be other causes, e.g. diesel exhaust oil of poor quality or in insufficient quantity. Ultimately, during the diagnosis, a defect on the computer or its software can be suspected.
Regardless of what has failed, this is one of the most serious mistakes to look at carefully. Otherwise, further damage to the exhaust system or even the engine itself may occur.
P244A – DPF differential pressure too low (Bank 1) / P244B – DPF differential pressure too high (Bank 1)
The outlet pressure sensor in the DPF filter not only has to check its degree of filling. It also detects filter removal or malfunction. When the outlet pressure is too low or the pressure difference too high, the code P244A or B and the MIL lamp are activated. Automatic regeneration is suspended.
Removing the DPF filter is just one of the reasons. The DPF filter and the pressure sensor can be damaged as well. The code will indicate a leak in the sensor cable or an exhaust gas leak before or near it. It also disturbs the pressure value.
P2458 – DPF regeneration time / P2459 – DPF regeneration frequency
During the automatic regeneration of the DPF filter, the exhaust gas temperature increases, which facilitates burning of soot and carbon deposits. In order for it to occur, the engine must maintain increased RPM for min. 15-30 min. However, with urban driving style and too short time at higher revs, self-regeneration is not complete. As a result, the filter is still clogged. As a result, the computer reads the discharge pressure outside the norms.
Incorrect regeneration time can be caused by a defective filter, pressure sensor or short circuit in the electric circuit. Other reasons are bad or too little fuel exhaust fluid. It is also possible that the on-board computer or its software has been damaged.
Regeneration of DPF must take place not only for a limited time, but also with appropriate regularity, guided by the pressure sensor readings. All causes that cause the P2458 error code can also trigger the P2459 code. Self-regeneration usually takes place every 300-600 km, but when it is interrupted, the DPF will not reach sufficient throughput. Therefore, it will have to be repeated more often.
Examples of DPF error codes – summary
Most often, the malfunctions that display the error codes associated with the DPF filter and this section of the exhaust system are associated with a clogged filter or sensor malfunction. When diagnosing, you cannot rule out leaks in the system or short circuits in the electrical circuits. Not even malfunction of the diagnostic computer.
Some of the errors result from the selection of unsuitable or poor quality consumables, e.g. engine or diesel oil, or simply from wear. Some of them are soft code and are canceled after resolution of the cause and subsequent measurement.
The lighting of the DPF indicator on the dashboard should be a sign for any driver who needs a longer ride at increased speed to complete self-regeneration. If this does not help, it is necessary to go to the diagnostic station and read the error codes from the computer.
See also the second part with the codes P0470, P2002, P2003, P2031-36, P2452, P2453, P2454 and P2455.