I have been having trouble finding the obd port on my older 90’s xj (91) and was curious if folks knew where it was so I can scan my onboard computer for any codes. Heck does that year model even have one?

 

doesnt have one to my knowledge youll have to look at how much times the check engine light flashes to get codes

 

OBD II ports were not introduced until 1996 for Jeep. For a 91, you will need to use this technique to read codes if your MIL light is on.

https://www.quadratec.com/jeep_knowl...article-24.htm

 

91 through 95 has an OBD1 Chrysler port connection under hood by pcm. I am not sure what live data you can get with the right scanner, but as said above post's codes can be had with key method. I would think you could get live data, even renix has that capability. I have a Snap on mt2500 with the Chrys obd1 connector, just never had a 91 years to see what I can get live data wise.

http://www.xjjeep.com/2007/09/24/obd-codes/

 

it doesn't have one but you can do a diagnostic test to it by doing this:
1.) Turn key to on do not start then turn to off then back to on then back off then on again and leave it there.
2.) The check engine light will flash then off with a long pause then on again
3.) Here's how to read the codes are all 2 digit codes each time the checkengine light flashes that's a number so 28 would be 2 fast flashes a pause and 8 fast flashes