xJJx

Hello, I am having a problem with my del sol running rough. The guy i bought it from installed a d16z6 and never wired in the vtec. So i wired the vtec up and replaced the p06 with a p28 while I installed a new clutch. When I went to start up the car for the first time after, It was running a little rough which i know is expected since the ecu's memory had been replaced and about 30 seconds into running the check engine light comes on. I turn the car off and go to find the harness underneath the passenger side dash by the ecu and it is no where to be found. I even looked under the hood and under the driver side dash for it thinking maybe someone moved it but still nothing. How would I go about adding this in again so i can read the CEL code thrown? I'm assuming its two wires off the ecu but which ones?