Deactivate cat heater? A look at engine control and the environment!

Thomas Wachsmuth 10 November 2023 Car repair & tuning guide

Reading time 4 Min.

This is at the heart of modern vehicle technology Catheats, a process that occurs with the cold start of the engine is linked. Some people are annoyed by the significantly louder engine noise. But why is that? Deactivation of the catalytic heating problematic and often even harmful for the engine? When starting an engine from cold, the components are like this Lambda sensors, not yet ready for operation because they have to reach a certain temperature. In this “blind flight”, the interaction between ignition and fuel quantity must be optimally configured. Will the process from the Motor Control removed, the engine can run too rich or too lean, which “can” lead to long-term damage. If the software is well done, the risk of the engine being damaged is reduced.

Deactivate cat heater?

The Cat heating system plays a central role. It's primarily about that Secondary air system controlled. The process of Warm-up enrichment serves primarily to quickly heat the catalyst. The increased injection of fuel and the Ignition adjustment lead to excess temperature, which allows the engine to reach its operating temperature quickly. Interestingly, the changed ignition contributes to the flame front reaching further into the exhaust and thus the Monolith activated more quickly in the catalytic converter. Another positive aspect of cat heating is that it can achieve the required level quickly oil pressure, which is crucial for the lubrication of important bearing points.

Reduction of pollutant emissions

The exact effects on wear in the micro areas however, are difficult to quantify. The primary By the way, the priority during a cold start is Reduction of pollutant emissions by quickly heating the catalytic converter. Switching off the catalytic heating also leads to one increased pollutant emissions, to unburnt Hydrocarbon and a higher one fuel consumption. Some vehicle owners find the increased noise level and the sometimes existing Exhaust smells during a cold start, especially in conjunction with modifications such as one downpipe, Chiptuning and Sports exhaust systems, still annoying.

Deactivate catalytic heating through software?

It is possible, the catalytic heating software changes to deactivate. This prevents the engine from revving up unnecessarily during the cold start phase. However, this practice is common illegal, unless the software is official registered and authorized is. Pollutant emissions should be reduced as quickly as possible through catalytic heating. To do this, the speed is increased, more fuel is injected and additional air is blown behind the exhaust valves in order to quickly bring the catalytic converter up to an operating temperature of ca 450 ° C bring to. In summary it can be said that catalytic heating is crucial for the engine and the environment. Although deactivation can reduce the noise level, it often has consequences for the service life and environmental impact.

Catalytic heating is a process in which the engine increases the exhaust gas temperature in order to bring the catalytic converter up to operating temperature more quickly and reduce pollutant emissions.
In some vehicles, catalytic heating can cause the engine to run rough, increase idle speed and increase fuel consumption.
The catalytic converter heating can take different lengths of time depending on the vehicle model, engine control unit and outside temperature.
Catalytic heating can be used in vehicles not for VCDS (VAG-COM Diagnostic System), Carly, Bimmer code or OBD Eleven must be deactivated because it cannot be used to change any parameters in the engine control unit.
Deactivating the catalytic converter heater may result in loss of warranty, deterioration in emissions levels, damage to the catalytic converter or an error in engine management.
Deactivating the catalytic heating is therefore not recommended and should only be carried out by professionals.

The following note is essential: For safety reasons, tuningblog recommends all repair, inspection and maintenance work exclusively to be carried out in a specialist workshop! Although our information is summarized to the best of our knowledge and belief, we cannot assume any liability for the content. All information is therefore "without guarantee".

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