My intention is to use your lambda shield to check lambda probes, without being connected to the exhaust manifold. To do this, I have thought of building a closed cylinder where the air is extracted with the help of a vacuum pump. As the measurement chamber measures the oxygen content, I think that ...

Would it be possible to simulate the operation of the probe, without being inserted in the exhaust? For example, inserting it into a vacuum chamber in which the air pressure and therefore the amount of oxygen can be reduced.