multiple errors please help!!

[undermountavery]

I have been battling my truck off and on for going on 3 years now. It runs very rough. It coughs spits and sputters, almost like its loading up on fuel. I have multiple codes logged. P0135, P0155, P0305, P0336, P0452. The truck has had the cats cut out. I've tried replacing the crank sensor in the past with no change in performance. Ive tried replacing the fuel pressure regulator, fuel filter, plugs, wires and the ignition coil on cylinder 5. Nothing has helped. I've been told to reinstall cats and change O2 sensors. I don't know which way to turn or where to begin diagnosis at. The engine started running rough out of no where going down the road. All help and information is much appreciated!!!!
Thanks,
Matt

 

[smokyjoeko]

On my 2004 front O2 sensor went bad and caused rough running.