Have the OBD port, pin are pinned out in the right location. Could get the port to work, so I grabbed an extra OBD port I have, gave it the two grounds and one hot it needs, tapped into the two signal wires (wht/blk and the tan wire) right at the computer itself. It communicates fine.

Go under the dash. Check the hot terminal and two ground terminals... they are providing voltage and grounding fine. But port still doesnt work. Then I ran a wire from the computer itself, to the corresponding pin on the port. Doesnt work. Figured having the stock routing of the wires and the direct line to PCM piggybacking on top of that may cause interference - so cut the stock wiring to take it out of the loop.

So now we have tan and wht/blk wire runnign from port to pcm, our one hot and two grounds... just like I pick it up under the hood... still no comm.

Any ideas? What did you V6 swap guys do with your port?

 

I ran into this same problem when I swapped the 93 drivetrain into my 94 V6. It's been a few years but I know that I had to run a wire from the PCM. I'll take a look today and see exactly what is was. What is your swap?

 

alright, just checked. It is not a wire from the PCM. There is a purple wire off the DERM that will likely need to be run to the data link connector. The placement in the DLC is bottom row 3rd from the right. This is the diagnostic request signal which is needed. I'm not sure how far along you are with the swap but if you haven't already I can't emphasize the importance of having a Helm manual. That book has answered 95% of the questions I ran into with my swap. Good luck!!