'95 JGC Limited O2 sensor need help

[hannalynn]

My jeep was idling really high and basically accelerating on its own. We took it apart and found the Oxygen sensor wasn't working. So my dad replaced it and the next day it went out again. Now it's just disconnected and the "check engine" light is constantly on. If I take it to the dealer with a new O2 sensor in it they say there's nothing wrong. but if I take it there when the O2 sensor isn't working they tell me that I need to get a new one. Does anyone know why it keeps going out?!

[msdz]

A # of reasons why it could be going bad, most of them are due to other sensors. If idling high my firstthoughts would be Idle Air Control Valve(IAC), this controls how fast the engine usually idles. If the O2 sensor you just replaced is good then the IAC may need to be replaced or the intake may need cleaning where the IAC goes in at.
Second thought I would have may be the Throttle Position Sensor(TPS). Sometimes but rarely this can cause a vehicle to idle at high RPM's. Most of the time this will cause the vehicle to have a surging in the engine though, high then low back to high RPM's.