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  1. Car
    2. :
  2. BMW
    3. :
  3. Serie 3
    4. : Checking the operation of the secondary air system

BMW Serie 3 - Video tutorial

Model: BMW Serie 3 E46 - Years 1998-2006
Part: Pump
Operation: Checking the operation of the secondary air system

In a petrol engine, many harmful substances are formed especially during the cold start phase (when a very rich mixture is required, i.e. with excess fuel): the blowing of secondary air directly behind the exhaust valves into the gas manifold exhaust, significantly reduces these emissions. The secondary air system therefore consists of a pump (positioned near the washer fluid reservoir) and a non-return valve that prevents exhaust gases, condensation or pressure peaks due to failed ignition, cause damage to the inside of the secondary air pump. The most frequent operating anomalies of the secondary air system are: the noise of the secondary air pump or the non-functioning of the same. In this case it means that the exhaust gas condensate has penetrated into the pump due to a failure of the non-return valve: for this reason, in case of anomalies it is always necessary to check all the components. To check the operation of the secondary air pump, it is possible to disconnect the plug and power it directly (but for no more than 90 seconds, as the pump has not been designed for continuous operation): if the pump does not work or it works by making scraping or whistling noises (so to speak, it looks like a vacuum cleaner), it needs to be replaced. The operation of the non-return valve can be checked with a manual vacuum pump in the disassembled state (disconnect the connecting hose between the secondary air pump and the valve): if the valve does not open when there is vacuum , must be replaced. Also, if the vacuum applied with the manual vacuum pump decreases, the valve diaphragm is not tight.


Posted on 28 June 2023 by ScegliAuto

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How to reset the service in the Opel Antara?

As we can see in this tutorial, resetting the service in the Opel Antara is an extremely simple and fast operation. Before proceeding, of course, we must have completed all the planned maintenance work. We start by inserting the key but leaving it in the initial position, after which we keep the accelerator pedal fully depressed and at the same time turn on the instrument panel, not the engine. At this point, we release the accelerator and press it 3 consecutive times, always all the way. We then restart the panel to verify that the procedure has been carried out correctly.

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by ScegliAuto

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