Can't remember if I ever got this figured out before. The dealer couldn't tell me why. I replaced my original leaking PCV hose on my 99 with some high quality silicone hose because I thought that's what was used. But I think it's a little too big because I'm hearing some leaking from it, but there's no holes or cuts in it. I just think the hose inside diameter on the intake port is a little big. Isn't affecting performance. The original hose I took off had a generic part number on it that all the other emission hoses under the hood had. I figured it was some kind of bulk hose used at the factory. I ordered one from the dealer by the VIN and they sold me the common 90 degree bend hose part number 53008675AB. Where that one goes mine has a rubber plug over it. My original one wraps around the back of the intake to the driver's side intake port. Anyone know why they did that? What kind of hose should I be using? Most I've seen use the 90 degree bent pcv hose but I have seen others like mine. I'm just wondering what the reasoning behind it was, if any. Does it matter if you swap from side to side?