So here's the deal. I bought my 96 XJ a few months ago, and it has to pass emissions and inspection before I can register it. So I took it to get tested, failed due to an O2 sensor failure. So I replaced the o2 sensor drove it for 100 miles took it to get tested again, failed due to o2 sensor not ready. Was told to "drive it some more". So I did... 500 miles more. Took it back, still failed, same reason as before. This time they told me to just Google the drive cycle and complete it that way. After googling it, I really don't see how I haven't completed it by now. But then I noticed this little gem of information in the document I found "Original 1996 Chrysler vehicles do not maintain OBD2 readiness after engine shutdown, however this is a fix that is available at a dealer." Does this mean what I think it does? Every time I shut off my engine it resets everything? Does that mean that the drive cycle has to be completed, then driven to the emissions tester, then be tested, all without the engine being shut off? That doesn't seem like it's right to me, but I can't figure out why I can't pass emissions. Thanks for any help.

 

Yes, that sounds like a firmware issue that can be resolved by the dealer. There was a recall along the way too for O2 sensor issues too.
Microsoft Word - E22 Owner.doc (jeep.com)