Help with post-cat 02 sensor wiring on 99 TJ
 

In tracking down an over-rich condition, found the pigtail and connector
for the rear, post-converter 02 sensor on this Wrangler were missing (due
to an altercation with a terrain hazard or road debris of some kind) and
replaced with permanent patch wires. I >think< they were connected
right, but I don't have a manual, and the problem apparently started
about the time this patch was done, so I'm redoing it, at least until I
can find a repair harness (n/a from Walker, btw) from a dealership or
junkyard.

The sensor has 4 wires: 2 white, 1 black, 1 grey. I presume the 2 whites
are the heater wires, but I don't know which of the black and grey are
sensor cathode and anode, respectively.

The harness wires are: Red/white stripe
Black/Yellow stripe
Brown/White stripe
Black

I get +4-5 volt across the Brown/White w/either the Black or the Red/
White, so apparently the Brown/White is the hot wire for the heater, and
the other two are grounds, but I'm not sure which is heater ground and
which is sensor ground. Presumably, though, in any case, this leaves the
Black/Yellow as the sensor +.

Does this sound right? Anyone have any ideas which ground is which on
both the harness and the sensor, or have a wiring diagram they could
check for me?

Probably find the real problem is a bad fuel pressure regulator, cold
start valve, or leaky injectors, but have to straighten this out
regardless.

Many thanks in advance,
jbdigriz