Exhaust after removing the catalyst - what could be the reasons
Content
It is not difficult to cut out the exhaust line component: this can be done by yourself or in car services. In Russia, such an action is not regarded as illegal if only one group of lambda probes is installed in the car. But even with a full set of oxygen sensors, car inspectors do not show increased interest in the catalyst.
Exhaust gases burn out in the catalytic converter of the car. The part responsible for the cleanliness of emissions into the atmosphere is removed by many drivers. The dynamics of the gasoline internal combustion engine (ICE) immediately increases, fuel consumption is reduced. But here a problem arises. The driver notices: as soon as the catalyst was removed, smoke appeared from the exhaust pipe. What is the cause of the phenomenon, and how to return the exhaust system back to normal - the topic of discussion in the driver's forums.
Why does the car smoke a lot after removing the catalysts
Converter-neutralizer (catalyst, CT, "kat"), located between the motor and the muffler, is made in the form of a metal pipe with ceramic honeycombs inside. The latter are coated with noble metals (more often - platinum), which causes the high cost of kats.
Smoke after removal of catalysts
The element is installed between the first and second groups of oxygen sensors (lambda probes), which control the parameters of the exhaust gases: temperature, content of harmful impurities. Honeycombs create resistance to the flow of exhaust, slowing down their speed. At this moment, on the spraying of honeycombs, the afterburning of gases coming from the engine cylinders occurs. As a result of a chemical reaction (catalysis), the toxicity of substances emitted outside is reduced.
After removing the CT in the exhaust system, the following occurs:
- A large amount of gas is expected, so strong colored smoke comes out of the muffler.
- The engine ECU, confused by the distorted information from the sensors, gives the command to enrich or lean the air-fuel mixture for the engine cylinders. Which is also accompanied by smoke.
- The backpressure in the exhaust assembly changes. It is offset by increased oil consumption. Therefore, the exhaust structure becomes different, and the motorist sees the plume behind the car.
If the appearance of smoke has received a logical justification, then the color needs to be dealt with separately.
Varieties of smoke from the exhaust pipe
After removing the kata, it is necessary to correct the "brain" of the machine - to reflash the computer. If you don't, expect a "tail" in the following colors:
- Black smoke indicates that the mixture is too enriched with gasoline, which goes into the cylinders. Not having time to burn out, part of the fuel is thrown into the exhaust line. Here the fault lies with the electronic engine control unit. Having made high-quality firmware, you will get rid of the problem.
- The blue or gray-blue color of the exhaust indicates excess oil in the tract. An excess amount of lubricant appears due to the increased back pressure after the removal of the catalyst. The solution to the problem is to install a flame arrester in place of the cut out element.
- White smoke from the exhaust pipe after removing the catalyst appears from the ingress of coolant into the system. Although CT may not have anything to do with it: perhaps it is condensate soaring.
In order to more accurately determine the cause of smoke, you need to notice at what speeds and speeds the phenomenon occurs: when regassing and accelerating the car, at idle.
What to do if the car smokes after removing the catalyst
It is not difficult to cut out the exhaust line component: this can be done by yourself or in car services. AT
But even with a full set of oxygen sensors, car inspectors do not show increased interest in the catalyst.
Exhaust smoke
However, you need to understand that the removal of kata is a gross interference in the design of the car. This entails the appearance of troubles: smoke of different shades, a strong smell and extraneous sounds from under the bottom.
After deleting an item, take the following steps:
- Install a flame arrester or a stronger in place of the neutralizer, which is much less expensive than the catalyst. This applies to cases where the removal of the part was a necessary measure (for example, after a breakdown).
- Reconfigure, or rather, disable, lambda probes. Otherwise, the Check Engine error will be on the instrument panel, as the engine is constantly running in emergency mode.
- Modify engine ECU program, upload new firmware.
The benefits of cutting out the catalyst are small, while the problems are much more significant.
