Vale were the dominant force in the opening stages and Justin Richards should have opened the scoring before McCombe did in the 11th minute.
Rob Taylor's left-wing cross was neatly side-footed into the path of the big centre-back who bundled the ball into the net from point-blank range.
Wycombe were second best, but they were transformed after defender Dave Winfield headed in Stuart Beavon's left-wing corner to equalise five minutes later.
Both sides went for it at the start of the second-half and Vale regained the lead following Gary Roberts' free-kick from the right flank in the 61st minute.
The ball dropped nicely for McCombe at the far post and his scuffed volley looped up off the outside of his right-foot to send the ball into the opposite corner of the net.
Source: PA
Source: PA