miss then no miss

[Just me]

Hows it going? Ok when my car is cold it idles ok but feels like its missing a cylinder under any acceleration, then all of a sudden it'll kick in and run smooth. After a few minutes it will miss again. I reset the computer and ran the KOEO test. All it told me is that the car was too lean so I adjusted my fuel pressure and still had the same problem. When I ran the test again it told me it was too rich. DOH! I adjusted the pressure again and the puter liked it this time but I still have the problem. The car misses one minute and then runs strong the next. Very unpredictable and hard to solve. I've changed a number of things to no avail. Any suggestions? Oh, I did notice the fuel pressure needle pulses.
Thanks in advance.