Got the right personality key in the OBDII adapter?

I don't recall just offhand which wires are supposed to do what on the connector. Wiring diagrams will show it though. If you don't have a service manual for your truck yet, get one here. Wiring diagrams are in section 8W.

 

Did you happen to look down the throttle body? Oil pooling means your plenum gasket is shot. This will cause misfires.

 

No! Because I'm dumb and didn't even know this was a thing.....but the second I read that I thought oh that's what that weird extra port on the OBDII adapter must be for.....

Turns out my brick came with most keys 1 thru 12. Well, from searching the web it looks like I need a K13. My luck had to run out eventually! But I've got a K13 on order.....

Appreciate everyone's advice on obtaining misfire counts from these trucks!