Follow the wiring harness from your ecu up and there should be a split and a plug that branches off from that. Insert two ends of an opened paper clip into the plug and count the code that flashes in your check engine light. Do a search, pulling CEL codes has been written up a lot on all of these Honda boards.

Good luck with your project. I just swapped in an 0BD2 JDM D15b vtec engine into my 94 Si, and it's a great engine. Probably going to stick a small turbo on it later this year. That engine isn't going to run well with a stock P28 ecu though. Get a socketed P28 or converted P06 ecu and find someone to burn you the right basemap for that engine. That engine is a lot different from a D16z6, the redline is higher at 7700 rpms. I'm also going to be using higher octane gas from now on too.