Regretfully, I neglected my 1993 300 I6 for a while and now I am trying to nurse it back to health. It started running a little rough. After checking and changing various things. I concluded that my cats were stopped up. I should also mention the weird smell coming from my exhaust. I cut my cats off and ran my exhaust straight to the muffler. The truck seems to be running better but its still not right. Is it possible to run these trucks without the cats or does it throw off the O2 sensor too much? When its cold it bogs down if you get into the gas pedal too hard. Once its warm it does much better, but not as smooth as it once was.

 

You have other engine issues that contributed to the cats melting down. Fix that and problem solved.