I need your help, I have a 00 Si with B18C Block on rebuilt B16A head. AEM Cam gears, A-FPR, Intake. P72 ecm with a funky lookin jumper harness.

Problem: Car when started, idles from 1500 down to around 850. I will let it sit and warm up until idle drops as close to 750 as possible before driving.

Sometimes, while driving and under throttle (regardless of gear), it will unexpectedly lose power (it feels like just before you stall out when still learning to drive standard.) I maintain throttle position or increase slightly and finally it will regain power and drive very funky.

I referred to a friend who works at a Honda Dealership in maintenance and he suggested I try to check the IACV. I started car, let it idle to 850(lowest it would go) then pulled electrical connector for IACV. it will still idle and fluctuates between 950-850 without connector in place. Still experiences issue once in a while when driving.

also worth noting, that after dark, everytime i turn the car on, it idles at 1600~


please give me any suggestions whether new harness, etc.

thanks for your help guys!