MY 2009 CAPRICE RPM METER GO UP AND DOWN

THIS COMES AFTER DELETING THE EXHOST SENSORS

Tom's vould be right! If your using an aftermarket 02 it will send wrong info to pcm causing less more to fuel ratio. Thus allowing car to fluctuate. But best way to know for sure is to do a live data from an Obd2. Shows everything like fuel, air ratio, timing etc. So your not going in blind.

But more than likely it is the o2 sensors