flat spots in powerband ka24de??

[Devens240]

Yesterday i put in a new O2 sensor, new fuel filter, and cleaned the iac valve. sinve then it seems to have a flat spot at like 2500 rpm's, and runs like crap when its cold. and suggestions?

[240sxScores]

Did you take the IACV valve off the back of the intake manifold?? try letting it sit with negative hookup un hooked from the battery.to reset the car.