@SuperSteveEXC -- If the dealer used a tuner and did it right then you shouldn't have to tweak the TPS, but it never hurts to make sure it's in the proper position. I would judge by how it runs. If it runs great then no need to fiddle with it, if it feels lean on bottom then tweaking the TPS can help. @scott72 -- The purpose of the screen is to reduce sound so I imagine that removing it is going to increase the volume. I'm like you, I want to be as stealth as possible, so I left mine in and it runs great.