Hello, we are planning tour to Peru on September 15, Lima->Arequipa->Colca->Puno->Cuzco->Sacred Valley->Machu Picchu. Is it good time for such tour? Thanks.

Pretty much the perfect time. It is towards the end of the dry season in the Andes which runs May to October. September will see clear blue skies and no rain with fewer crowds than in June and July. Lima will likely be a bit cool with fog and drizzle due to the Garua which hits that part of the coast around then but you probably won't be spending much time there anyway.