1990 Buick Riviera Won't crank sometimes?

[Demarcus]

I went to start my car this morning and the car wouldnt crank dash lights comes on but nothing fron the engine. when I turn the key to crank I hear a click come from under the dash it sounds like a relay I also hear the fuel pump. But after I let it sit for like 5minutes it will start sometimes. Im thinking its the VATS security the lock cylinder or the key but i just replaced both of them along with the starter and battery about a year ago. Is there anway I can test the cylinder or key? And if it is the lock cylinder or key is there anyway I can bypass it with out messing up the car? I have a 1990 buick riviera 3.8 V6