Rough Idle/shaking, Blinking Cil, Replaced Ocv 4 Mo Ago

[fruehling]

Codes:

p0301

p0303

p0304

p0305

p0172 (system too rich bank 1)

Determined that OCV needed replacing a few months ago and that solved my problems for awhile. Still a little hesitation on acceleration, but mostly good.

Have had small oil leak since forever, so bought an additive during last oil change 10 days ago (Sears) that was supposed to fix it.

Suddenly CIL came on and is usually blinking, and car really shakes at certain tork.

Coils? Plugs? Wires? Change the oil again to get that additive crap out? Please tell me not OCV again. Any thoughts? Help is greatly appreciated. Still runs consitently so i'm not without transportation.

[fruehling]

No takers? ANY help is greatly appreciated. I'm thinking the system too rich could be the cause??