Hey everyone,
I was looking at one myself (https://www.performancechiptuning.com/stage-1-performance-chip-module-obd2-for-nissan/). I am a little skeptical, but I don't find it impossible. I had a 1996 Grand Am that someone programmed using a laptop and the OBD2 port. This doesn't appear to be one of those cheap resistor ones I would find on eBay. Could the instructions for a tune be simply programmed into a dongle? That would be great! To chip my 95 525i, I have to physically remove a ship in the electronics box.
C.M.