Like I said, get a cap with brass inserts. Worth a shot anyway. DuraCrap from autozone. Is that where you got the TPS also? Get a Haynes manual and a DVM and you can check all the sensors. Also , doing this won't hurt.
http://dodgeram.info/tsb/1998/18-48-98/18-48-98-v8.htm

 

Hey anythings worth a try, thank you. Ive noticed it only does this after warming up and if i ease the throttle it wont do it at all

 

After warm up can be the o2 sensor. You need to eliminate common things. Check plenum regardless of cat status. While the TB is off clean it and the IAC. Get a Haynes and check the sensors, like ECT. Crank sensor is the only hard to check sensor. But easier since it does run. Could also be the PCM. Try aiming a blow dryer on it to get it warmed up, and see if it has the symptoms right off the bat. You simply have to start eliminating things without spending money at first.

 

honestly the cat doesnt "spoil"... If it wasnt plugged at all and you could see through it as well as you say it would have worked once it got up to temp as long as conditions were right.... If it wasnt getting up to temp or your emissions was still failing than you may have had some other issue causing it to run too rich (or lean actually) both will effect how well the cat works...
the metals or ceramics inside are designed to get super hot and superheat the exhaust gases in turn making what passes through cleaner with less unburn fuel and hydrocarbons...

so I would concentrate on the multiple misfires because thats the real cause of your problems...I recently fought the same issues only mine were under load only.... I would check your compression.... as well as try pulling one plug wire at a time while its running and look for the one that has no effect on how it runs (if any)
If it only runs bad after warmup try swapping your two 02 sensors...the precat one is likely failing and causing the truck to run rich or lean...

 

Compression is 125 across the board. There is such thing as a Poisoned cat BTW. This happens when s*** like unburnt fuel coat the working surface of the honeycomb. So "honestly" the cat does spoil...look it up...why do you think misfires f*** them up..Why do you think cat's get replaced...Anyways, i have only one o2 sensor. Im sure i should have two, one in front of cat and one in back. i just have one.

 

I've heard people mention what your saying ...and I've heard other people say they can almost always be repaired easily and the poisoning excuse is overused by greedy shops..

Its actually fairly difficult to poison them unless your dumping coolant or zinc into them somehow or running lead in your fuel) and all those things would take out the o2 sensors first.
I've heard of them getting saturated with unburned fuel or oil but was always told a long drive would burn that out once the issue is fixed that causes the contamination.... . and obd11 vehicles are designed top flash the check engine light when misfiring occurs to prevent conditions from getting bad enough to cause something like this.

Hell a lot of mechanics wash them in detergent and water or use lacquer thinner/ fuel mix at like 2500 rpms for 20 mins to get them hot enough to burn all that out of them. You can even use this method to clean them out when they are plugged and get them back in working order ... you can research that too.... hell you can find counterdicting information and ways of doing just about everything on the net...
Regardless how could you even claim to know the cat was "poisioned" and wont work when your trucks still broke and spewing unburnt fuel into it? iIs not in a properly functioning enviroment to see how it works (or doesnt)?

 

A 95 only has one o2 sensor.

 

I only have one o2 and its not an obd2 vehicle either. obd1. that came out in 98. Thing is i had a misfire for about 6 months or so, fixed that and it ran fine shifted fine.took it to inspection, failed. waited about 2 weeks, my tps went. fixed that. now this. so it was in proper conditions.im telling you the cats were done. changing o2 and checking other ignition parts
tommrow

 

OBDII was required on any vehicle built in 1996 and later.

 

yessir. I checked my plenum using a stick and paper towel, i scrapped the bottom and it came out black. not wet tho, kinda like built up grime or grease. smelt like fuel.