Ok well before I was getting a code for an o2 sensor wich was po138, bank 1 sensor 2 or w.e which is the sensor after the cat. I replaced it with a bosch oem o2 sensor. Did that 2 days ago, now my light just came on. I checkd the code, its the same thing, so any ideas on why its saying that? , did I replace the wrong one or something?? Also I have a slight rough idle, which feels like it is miss firing very slightly. But its been doing that for a while now, no codes for that, the only code is the one for the o2 sensor. But yesterday, when ever I start my rig, and start to leave my whole rig like boggs down and I let off the gas peddle and then its fine, after it does that it runs completely fine and I can go from a complete stop and accelerate with no problem. Things I have replaced recently is plugs, wires, distributor cap, rotor, air filter, and I just changed the oil and oil filter today. I also cleaned the throttle body and iac, I plan on cleaning the map sensor tomoorrw. So any ideas? I need some real help, also my exhuast is kinda put on half *** and is just clamped on and leaks a bit could that have anything to do with it? Could my cat be bad? Theres no bad smells or anything tho

 

Check the wiring and plugs to the o2 sensor. that could be your prob

 

You replaced the right sensor relating to the code, but the sensor itself isn't the problem.

As mentioned, verify that the wiring isn't damaged or burned for that sensor.

As for that sensor causing your symptoms, it is highly unlikely as the after cat sensor is there primarily to measure the efficiency of the catalytic converter. It is the upstream sensor that gives the input to the computer that affects fuel/air mixture. Your symptoms are being caused by something else.

High fuel pressure is something that (occasionally) can cause this code. I'd verify your pressure with a gauge and compare it to factory spec., which for a 1998, is 49 psi, plus or minus 5 psi.

You could also try a complete clearing of the code and the adaptive learning. I saw a couple of threads where this cleared the code completely after the fix was performed (new sensor). Here is more.
------------------------------------------------------------
This procedure is for OBDII Jeeps.

This six step procedure will erase the “Adaptive Memory” stored inside the PCM and allow a new “Adaptive Memory” to be developed. After performing this procedure the PCM will re-learn and store into Adaptive Memory your engines performance characteristics.

Perform these steps exactly as they are written, in the order they are written. This will cause the adaptive memory in the PCM to be erased and cause the PCM to go into Fast Learn Mode adaptive mode.

1. Disconnect the POSITIVE battery Terminal and touch it to ground for 30 seconds. (This is to discharge the PCM capacitors, which maintain the Adaptive Memory.
2. Reconnect the Battery Cable
3. Turn Ignition Switch to the “On” position but DO NOT start the engine
4. Turn Headlight “On”
5. Turn Headlights “Off”
6. Turn Ignition Key “Off”


The PCM Adaptive memory has now been flashed, or erased from the PCM.
When you start the engine it will be running off a set of pre-programmed values that come with the PCM from the factory. When you get the engine up to operating temperature the PCM will start to collect data for the “Adaptive Memory”. The PCM will collect data for Adaptive Memory for the first 50 warm-up Cycles.

 

Can bad fuel pressure cause the idle problem im having along with the bogging?

 

Any further help would be great

 

nobody??

 

Possibly. That is why I would take a few minutes and check your fuel pressure.

Troubleshooting is a "process of elimination". A number of sites recommend verifying your fuel pressure for this exact code.

 

I really think it is a fuel problem. im gonna check the fuel pressure today