If its a rear caliper....check and make sure the e-brake isnt on. Thats what happened to me.
1988 Mazda 323 GTX; 1 of 1,243 Imported
AEM CAI, VJ11 Turbo @ 20psi, 2.5" IC Pipes,
Corksport IC, CFDF Clutch, 2.5" Turboback, Konis,
Suspension Tech Springs, 22mm Rear Sway, + More.