Running problems with a 93 3.1 V6
 

I have a 93 Cavalier RS with the 3.1. The car was running great until last week as it warmed up it started sputtering when accelerating from a stop. It now has gotten worse it takes forever to reach speed ad the mpg has fallen off. Checked the cat it is a straight through design does not seem to be the problem. Checked the O2 that seems good. No check engine light. Will the MAP sensor cause these problems while the car was idling I moved the sensor itself and heard a change in the idle Checked vacuum at the sensor it was good. Any help will be very appreciated.