throttle not closing all the way

hey guys
i had a clogged up fuel filter the other day, and to get home i ran her without a filter for a few miles

im guessing thats where the issue came from, but the throttle doesnt want to close all the way
(i got her to idle at 750 in neutral, 600 in gear)

every once in a while , it wont close all the way, and hang around 1200-2000 RPM

the carb is a proform 750, basically a 4 barrel holley

i dont see anything in the way to mechanically stop her from closing, and there is a little tension on both the return springs (lokar set up)

is there anything i can do to clean, oil or grease the shaft to get it to operate smoothly?