1996 Chevy Beretta hesitation during acceleration

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1996 Chevy Beretta 6 cyl Front Wheel Drive Automatic 261KM miles

Hi,
I have a 1996 Chev Beretta z26 w/ 3100.
A few months ago I got an oil change and replaced the pcv valve, since doing that the car really hesitates while accelerating. It will rev properly and then aroung 2000-2500 rpms it seems to "stick" then it will grab then stick again the car is some what sluggish overall. It ran great before the new pcv. Also, the car runs perfect when cold, only kicks in when it heats up. The engine runs great in park or neutral, and the tranny isn't slipping
heres what i've done to try and fix it
3 Different pcv's
new pcv boot
new vaccum line to pcv
new fuel filter
new o2 sensor (bank 1 sensor 1)
dropped the trans pan twice (new filter and gaskit)
replaced the catalyc converter (new exhaust as well)
new mass air flow sensor