leon

so guys,
the verdict : new PCV Valve (second generation), this is the second time that the dealer changes this in my car. last september, the dealer had changed the original PCV Valve with a new PCV valve of first generation, based on audi's recommendation. he told me that the technician found a lot of water (condensation) in the PCV valve, so the water froze during the night and when I first started the car in the morning, the valve was full of ice, conclusion: the engine had not enough air to run ok (this explaine the up and down of rpm).

Oil consumption verdict:
I spooke with the technician who repaired my car concerning the Oil consumption. he told me that the new PCV Valve won't have a significant effect to reduce it. the best thing to do is to check the oil level every 2000 Km.

thank you for your contribution to this discussion