New to forum- so I thought I'd share.
I had p1491, p0130, and p0136 come on right after I bought my 2000 xj.
Printed off service manual pdf, checked the fuses in said manual, and mine were ALL screwed up.
After I replaced the fuses (some of the slots were missing fuses) my dash lights worked, and all engine codes went away.
Logic would tell you that something is goofey if you get a series of strange codes- what are the chances that all of your o2 sensors fail at the same time, as well as the purge solenoid. Fishy....right?
So start with the fuses - make sure they are the correct size, and in the correct slots.
That fixed my problem.