[bbottomley]

"Dying" sounds like an overstatement! Anything in the circuit from the coil to the plug in cylinder #3 could be causing those symptoms, and it shouldn't be major thing to fix. You can test a good bit of the stuff by substitution with a nearby cylinder.

My P030x from last year produced similar symptoms. Itwas caused by a broken connection within the plug boot.

 

[bbottomley]

The OP said p303, I'm assuming CEL code P0303 - clylinder 3 Misfire Detected. :smile:

Me too

 

[bbottomley]

Yes, the symptoms exactly match my plug cable problem of last year. As for the front O2 sensor, the only thing that made me notice it when it went bad was the CEL. Car felt quite normal. And though there is some confusion as to the CEL code you got, putting 2 and 2 together sure comes up with something like P0303, which means bad spark in cylinder #3.

 

[bbottomley]

Drive up to New London and I'll help you change them.