are the o2 sensors hooked up backwards? In other words, are the connectors swapped between the pre and post cat sensors?

Ever figure this out? I am getting this code now as well and the Indy has no clue what the issue is. They replaced the gas cap and light went away for a few weeks and now it is back. I cleared it this am and came back about 20 miles later.

You need to find a better INDY. A bad gas cap will produce an evap code/problem.

Check this guy post on the P1093.

http://www.xoutpost.com/bmw-sav-foru...xed-p1093.html

well to start of to much air=lean not enough air =rich
i had it were on bank to was giving me both codes even though the o2 were new NGK
so after some more reading these vehicle are pickie i bought 2 new BOSH o2 reset ses
after 10 miles no more codes but now i would get po430 for the same bank 2 WTF
with NGK only 2 same codes with BOSH only 430 code also the mass airflow controls the air to fuel mixture for both banks guys were using the k&n filter and the oil would get on the element and give the lean or rich code also if the upstream o2 is loose same
thing and at time even though the ICV sounds good when shaken it doesn't really mean it is good meaning it might not be opening or closing like it should on mine with out AC on i get a certain fuel trim reading then when ac is on they go down
but the rule of thumb is lean=more air than fuel rich=less air more fuel
a friend of mine with same problem did a adaptain reset with inpa and it went away

in inpa you can turn off individual injector. a leaky injector would also give rich code

P1093 since 10/2015
 

Just in case somebody is having the same problem, to make a long story short ,what fixed this code for me was replacing the post cat oxygen sensor Bank 2 Sensor 2 and I haven't even replaced the other post cat O2 sensor yet ,x5 is due anyway. Vehicle is 2005 X5 3.0 120,818. Original MAF,IACV,intact intake ,new fuel filter after reset and 200 miles mixed drive.
Hope this helps.

I've just started looking into these codes on my 2005 X5 3.0 as well and posted a video today:

https://www.youtube.com/watch?v=fykuAkjVI4g

loose oxygen sensor was all it was for me
 

to this day, P1093 has not been back, by this time ALL of my oxygen sensors have been replaced. The one replacement that cured it all was when i found that one of my oxygen sensors underneath was in fact off not just loose. replaced that and code was gone,even took my time replacing the other 3 finally the last of which I did last week.

Thanks for coming back to comment. Thinking it may be worth throwing in those post-cat sensors as well!