MPFI Swap problems

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LudeBoy

Slave to the EF
91 DX Hatch. PM6 ECU, D16Z6 Intake Manifold (at least I think that is what it is, it has ribbs on the top of it instead of the pgmpfi)

On to the issue. It runs great performance wise. The only issue is that it idles like shit, it stays above 2.5k at all times and goes to 3k until warm.

Things I have done to troubleshoot.

ECU is not pulling any codes on the stock map sensor located on the firewall. I swapped the connector to the map sensor on the z6 manifold. The idle came down but it was sputtering. I left it like this for a while until the ecu pulled code 1 (o2 sensor). I pulled all the plugs and they were all black along with the o2 sensor. I did a compression test while the plugs were out 190 195 195 190 excellent. I replaced the plugs with new ones along with the o2 sensor. I then cleaned the IACV with brake clean and rewired the old stock map sensor up. Same bs, still idles high.

Any takers on what the issue is?
 
Thanks for the replies guys... It ended up being the damned fast idle control valve. I bypassed the coolant to that thinking it was just to warm the throttlebody. I plugged the valve and it idles great now.
 
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