Have a 2004 WJ, 4.0L, 95k
I'm getting a check engine light, P0031 HO2S Heater Circuit Low Voltage Bank 1 Sensor 1.
The jeep is nearing 100k, so I replaced all four of them. Next day, I get the same code. Didn't have a chance to replace right away, it's been about a month. Check engine light comes on and off. Will be off for a couple of days, then on for a couple of days.
Today, clear the code, replace the O2, which I'm pretty sure is 1/1, let the Jeep idle for about 10 minutes, no light. Back out of my driveway, engine light comes back on, same code.
Any ideas of what I might check next? Looked quick for frayed wires, but didn't see anything.
This is driving me nuts!