Throttle body is sticking slightly every time I take my foot off the accelerator pedal, I tried to wd40 everything up, including spraying some down the throttle line as much as I could but I've located it down to the actual butterfly inside sticking and getting stiff each time. What would cause this and what would remedy it?
Very annoying, each time I pull off I have to push the pedal to get it to unstick
(Ive got the throttle body off too)

