96 EK swap idle problem

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I Just finished swapping a d16y7 into my friends moms EK coupe. I used a Y8 intake and exhaust manifold (old engine was a botched d16z6 block w/y8 head) and the idle keeps hunting between 1800 and 2000. Theres a hissing sound comming from underneith the manifold (like theres a significant leak) and im not getting any CEL's even with MAP, IAC VTEC pressure sensor and solonoid disconnected. WTF. Any help wpuld be greatly appreciated. This is also my first time doing a swap on an obd2 car.
Which throttle body are you using because I had the same problem when i put a Y7 throttle body on a Y8 intake manifold. If you compare them you should notice that the Y8 maniflold has a hole that the Y7 doesn't. Just block that off and the hissing should stop and the idle should go back to normal. Also which ECU are you using?
and this hole in the y8 manifold, where is it? Someone else mentioned blocking a hole on a previos forum thread but the location was vague.
Is the car an auto or manual because on the Y7 and auto Y8s use a different style IACV to idle and are you using the Y8 head on the Y7 block because a Y8 ECU won't correctly run a Y7. Also does the CEL light come on when you put the key in the on position?
I would start by bleeding any air out of your coolant. This is a common problem after a swap that causes a high and fluctuating idle. If there's no air in the system, next I'd grab a can of ether and spray a little around your vacuum lines. If it affects your idle, you have a vacuum leak. Might be a couple good places to start. Best of luck.