P0139 intermittent/rough idle

Jaybird91

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Hello , So i had an issue this week with the p0139. The stubborn 02 sensor was giving me problems. Scanned and reset twice. I drove on the fwy the second time with my scanner to make sure it wasn't pending. I then drove it to get smogged and it passed luckily. On top of that i have another question/theory.
Has anyone had this issue of rough idle and possibly misfire related code for some reason while using or powering there radio or headlights? i get a rough idle for a good moment while turning these electronics on when at a stop light in Drive.
04 V6 liberty - Thanks
 

LibertyTC

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P0139 O2 Sensor 1/2 Slow Response, best to replace the 02 sensor with NTK sensor.
Jeep is very particular about charging & voltages. Have you had the battery load tested?
Using a VOM what is the battery output voltage while engine running?
Rough idle or misfire, Have you tried installing new spark plugs ? Use ONLY NGK ZFR6F-11G gap .040 inch.
Eventually it may set a code for the misfire, which would be helpful.
If the Jeep is high mileage replace the coil packs, as it is considered a tune up item. I used Standard Brand, but Mopar coil packs are best.
 
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