2000 Rodeo Codes

My 2000 rodeo started to idle really low and then my CEL came on. I plugged in my computer and the 4 codes that showed up where 2 codes saying that bank 1 had gone rich and then the other two said that bank 1 had gone too lean. What would cause this and is there advice to rectify it.

Erratic idle & random fuel trim codes is usually the sign of a cracked intake manifold gasket. Search around this site for "intake manifold gasket" or "IMG" and you will find tons of stuff.
G/luck
Joel