So I got a ek and it's a stock ex with a stock y8 in the car. Car is throwing a cell of idle air control valve circuit. Change iacv with a known working one and same problem. When the car is cold, no problems, works as it should. After it warms up, it likes to idle smoothly at 1500rpm. Big problem is at very light throttle, it acts like a fuel cut then a j erk back on the throttle and over and over again, like it has to accelerate or decelerate, no smooth cruise. It doesn't do this when cold, or even after warm if it has not been to an idle for any time, but if I sit at a long light for a few minutes, that is when the problem starts. Any help would be greatly appreciated.