You dont always get a code for 02 sensor but that is always a possibility

 

The first code I had was the random misfire.
Then I changed the EGR valve, which fixed the problem temporarily.

The next code was the Right Bank O2 Sensor.
Changed this sensor about three weeks ago and there have been no problems since.

I do believe that the misfire was a combination of a sticky EGR valve and a failing O2 sensor.

 

It very well prolly was, glad you got it fixed

 

Just posted this on another thread ... your symptoms were identical to mine:

P0300? Check the two short ground straps that ground the valve cover to the head stud. They are under the plug wires for cylinders 3/5 and 4/6. Just repaired my passenger side ground strap last night (steel connector? C'mon Chrysler...) and it cleared my P0300 misfire plus the resultant P0132 O2 code. So far at least.

Just an easy thing to check. I suspect that the lack of valve cover ground was interfering with the operation of the coils since they probably need to be grounded. My misfire and codes were primarily at idle ... somehow at higher RPM the coils found a good ground.

(Fyi I also replaced my EGR preventatively while I had everything apart, so that could have been the fix, but I can't imagine how)

 

I removed mine when taking my heads off, i will be replacing them with something a little more sturdy!!! Thats for SURE!