The hang is from a vacuum leak. 1st check the seal at the manifold, Did you re-use the gasket any RTV?
2nd check all Your hoses, PCV, ect. are they plugged in? 3rd all clamps at all rubber joints. Get a propane torch turn it on and with the engine running place it near the expected leak. if there is a leak the idle will speed up. Long shot but if you used a 65m T/B cheek the Allen screw on the left of the housing it must be tight(closed). Hope this info helps
