91redb20ef

I have a 91 std that I b20 swapped a few months ago. I'm currently running into an issue where I am not getting a map sensor reading on Hondata. I have tried several map sensors I ordered an OEM one before I butcher the harness and run wiring directly to the ecu is there something else that could cause this issue? I have checked the polarity and I am sure it is correct. I have also since bought 2 ecus and another jumper harness to attempt to fix the issue