idle after head swap?

I had a headswap done with tw heads and 1.6 rr and my car seems to idle rough just sometimes. plus, i still have a problem with the cold acceleration, but that happened before the swap. anyway, I just tryed to pull some codes and it passed. Looks like my mechanic fixed most of my problems. But as far as the idle goes, do you guys think that I may just need a computer tune with the engine mods that I have or maybe just need some more of the supporting cast. fuel and air induction.

Thanks, hope you can help

Well it sometimes has sort of a surging idle. it will go up and down, This problem started shortly after that swap. It ran well and then after a couple weeks it started to surge and die, I took it to my mechanic and he got it to idle but it still doesn't idle right. he had trouble with it because of all of the modifications, he usually deals with oem equipment. It is drivable now but the idle bothers me.