85.5 944 Start/Idle

[clar521]

I just finished completing partial rebuild of my engine from a balance&cam belt break. It included replacement of the cylinder head, roller, tensioners,belts, and gaskets. When I go to start, it fires and dies. I can force it start with the throttle and butterfly @ 2000+ RPM but will die or stutter below that.
I then replaced the throttle switch and air flow sensor, triple checked every connection, vacuum hose, but same thing. Sometimes will idle at 200 & try to rise but dies. I was thinking maybe its the idle control valve or a fuel rail/injector problem. Any thoughts on the matter would be helpful. Thanks Alot.

Jason