Chevrolet Repair: rough idle, chevy s10, o2 readings

Question
i have chevy s10 2002 4cyl vortec model have changed plugs and wires. still has rough idle. high rpms runs fine.this model has no egr valve or pcv valve also dis ignition. any help would be appreciated.  joe,

Answer
Hi Joe.... try a good inj cleaner and a new fuel filter....use a good air intake cleaner in the air intake while running....check to see if the cat converter may be plugging up...if you can install a scan tool and see if it pops up any codes...look at O2 readings and see if they are within spec....these are just some suggestions...hope they help