My truck has just recently started to rev high at start and when i push the gas in park it goes up and lags to go back down and it even revs kinda high when in gear at stops some times any idea what this could be its not showing a code.

 

I'm no expert at this but I am guessing that it could be the Throttle Positioning Sensor..

 

Thats what my friend i guess ill check that out it makes it harder to stop my big truck cuz it doesnt rev down enough

 

Every time I start mine it revs up real high 2K RPM. Especially if air is on. It does come down after a little while. I have lean code on both banks. I have already swapped/cleaned a lot of parts and hoses with no luck so I kinda gave up on the lean problem. I think the high rev has been there since I bought the truck (June 2009).