Lots of great valve adjust procedures out there Steve. A great one put there by some really expert mechanics is on my website, there are good ones here too. Lots of help on that issue. Don't drive on any dusty roads with that cover on. Since the air under the hood is sucked into the engine due to negative pressure created by engine operation, whatever road grime that is under the hood is going right into the engine through those vents. It is why they only made that cover for a year and a half. But you know that, and probably only drive your truck on nice days on paved roads so you are fine. If you lived in Kansas, that wouldn't work AT ALL. Here, the paved roads have dirt on them due to the wind and topsoil erosion. Many a vented cover here has duct tape on them. I would love to 'load up the truck and move to Beverly', but I am too lazy.
