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