Volkswagen EA2 1 1, 1.6 changed the oil automatically, and the engine idling sound became louder! What's going on here?

Thank you for inviting me! After replacing 0W40, the fully synthetic idle sound becomes louder. Occasionally, it will happen when switching from mineral oil or semi-synthetic to all-synthetic engine oil. Because the viscosity becomes smaller, the computer has a matching and adaptation process. Run a few hundred kilometers first. If the idling sound is still loud, there is a problem. First of all, consider the problem of engine oil, but I believe you can master the deeper parameters of engine oil viscosity and won't buy fake engine oil. Secondly, consider cleaning the throttle and matching the computer. The best way is to remove it, clean it before and after, dry it and then install it. The fluidity of the same type of gray shell is second only to Castrol and better than Mobil. Under normal circumstances, this problem should not occur.