Take the belt off and try it, if it's that it's one of the pullies or tensioner.
It could also be the rotor hitting your distributer cap, mine usta do that for some odd reason.
As far as the knocking I get a feeling it's your harmonic balancer or something that threw the crankshaft outta place or off balance. Mine did the same exact thing when the rubber from inside the balancer tore apart.