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blackattak

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Discussion starter · #1 ·
OK this showed up this morning. Engine Light is on solid so I believe it is not a major issue. Very cold overnight & when I started up this morning (started easy enough) & it hesitated a bit when I pulled out of the driveway & on the street the warning light was on. Did the 3 key turn tricjk to get the code. What should I do about it? Anything to really worry about?
 
Not a huge deal. It's a post-cat O2 sensor so it is primarily there for keeping the catalytic converter in check, it also plays a part in the A/F ratio, but not to the extent that the pre-cat sensors do.

The heater element basically makes the sensor warm up faster to get you out of open loop(closed loop is more efficient). I can't remember how many O2 sensors are under a TJ in all, but if it's 4(as opposed to 2), then check your PDC as there should be an O2 sensor heater relay, which supplies the voltage to the 1/2 and 2/2 O2 sensors heater elements. The 1/1 and 2/1 sensors get it directly from the ASD(auto-shutdown) relay. All are PCM triggered, but I doubt the PCM could be the problem as it's only the 2/2 sensor throwing the code, I'm not positive but I believe both the post-cat O2 sensors are on the same circuit so aside from the O2 sensor itself going bad, it could be the wiring.

In a nutshell:
A) Check the O2 sensor wiring for any opens, shorts, etc anything visually wrong with it.

B) Replace the 2/2 O2 sensor(bank 2 sensor 2).

You may find your gas mileage takes a crap until it is fixed.
 
Discussion starter · #3 ·
Only 25,000 km on it so I`ll let the dealership look after it on Monday.
 
Discussion starter · #4 ·
Would have taken it in today but now light has turned off. Won't worry about it for now. Turned on during cold snap, above freezing last 2 days & now off?
 
i have the same problems man, did you do anything about it? or did the problem procede on cold days? im about to replace mine soon
 
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