If it's a manual, there is a little plastic cup-like grommet that the shifter rides in that can break and bind the shifter. Don't force it into gear! Remove the shifter boots and the 3 or 4 fasteners holding the shifter in, lift out the shifter assembly (being careful nothing drops in) and the white plastic grommet will be visible. It looks like a shotgun wad. Mine went out at 202k. Easy to inspect and/or replace.