When the Air Escapes from the Petrol Engine

After the cold start, petrol engines are real pollutants because the exhaust gas aftertreatment systems are not yet fully functional. In particular, unburned hydrocarbons (HC) and the respiratory poison carbon monoxide (CO) cannot be converted in the catalytic converter, which is still cold. Additionally, after a cold start, the “greased” fuel-air mixture does not provide enough oxygen for effective pollutant reduction. To compensate for this lack of oxygen, petrol engines have a so-called “secondary air system”.

Using an electric pump, this system mixes oxygen-rich air with the exhaust gas via channels in the cylinder head for a maximum of two minutes after a cold start. This means that enough oxygen is available after the cold start and the catalytic converter reaches its working temperature very quickly:

Actually a very useful system, which should protect the environment and us humans from harmful exhaust gas components - if it were not switched off most of the time. As a result, this leaves the polluted exhaust gas enough time to settle in the secondary air channels in the cylinder head and to block these channels.

However, if the system is then used, the air no longer flows through the blocked channels. The engine control system recognises the problem and prompts the driver to visit a garage via the engine warning light.

Until now in such cases a long and costly cleaning of the clogged secondary air channels was the standard answer. The engine had to be partially disassembled and the components were cleaned through a dirt-intensive process. This would take a whole working day or even longer.

TUNAP has now developed a significantly more efficient solution to this problem: with the TUNAP Secondary Air Cleaning Tool the cleaning process is extremely user-friendly and clean and can be completed in about two hours.

To do this, the TUNAP tool is simply connected to the secondary air system, the can with the TUNAP cleaner is inserted into the tool, the engine is started, the secondary air system is activated - and after a short time the “airways” of the secondary air system are clear again.

This system is also ideally suited for the preventive treatment of the secondary air system, in other words, before the engine warning light prompts the driver to visit the garage.

As with other problem areas on the vehicle, TUNAP also offers a simple, quick and inexpensive cleaning solution for the secondary air system instead of the complicated, dirt and cost-intensive variant.

The engine control light is flashing, the secondary air ducts are blocked? Then ask in your garage for a clean with the TUNAP Secondary Air Cleaning Tool and save time and money. In this sense: TUNAP works.