the engine is a b16a1 with a 94 GSR head. i used crome to write a stock b16 p30 map minus o2 sensor, ELD, and knock sensor on a p28. the problem is that when driving under 25% throttle the car will just fall on its face all of a sudden then be fine. the idle also ***** up once and a while when it is warm (start bouncing to like 1500). when i take the intake tube off there is suction from the top hole when warm (i think its the iacv hole). i tried replacing the iacv with one i had but i dont know for sure it was good. my question is could the iacv create these issues or should i be looking for some other problem

 

bump

 

just by looking at the title and scanning your explanation..

sounds like a vacuum leak... and if not you have a miss...