recentlly i found a problem when looking at my brake front caliper. For wjhatever reason to brake pad on the outside, closest to the rim, is not releasing from the rotor. This is not allowing the wheel to fully spin, is it time for a new caliper? or is there anything i should try. The piston itself wasnt backing out either but we cleaned it up and now it backs off. Its hust the outside brake pad thats sticking. or Can this be cause by air from pushing the piston in. Im running out of ideas!!!