There aren't many parts involved in the "hinge" of a foot pedal so not a lot to cause sticking. The pivot is crude, so maybe there's some wear which lube won't help. The return spring can generate some friction so a bit of sanding and some grease on the rubbing parts. Or the rheostat can become sticky which a cleanup will help. You can cycle your pedal by hand and if there's an issue you can normally feel it quite easily. Does it cycle through it's motion smoothly?
I strongly suggest though that the trouble may be in the machine itself. If it's in need of a good cleaning and oil change, it can take a lot of current to get past the sticktion and get it moving. When it finally breaks loose the pedal is in a position to produce faster speeds. so it's really flying.