01 Jimmy 4.3L running extremly bad! AWE Rotten Eggs

Well Here I go!

My 2001 Jimmy SLE 4DR 4WD 4.3L V6 175,000+ is running like total A$$! Very violent when trying to start (Whole Motor Shakes), and when it starts, at idle until the RPM are increased the over 2000 RPM. Then it still stutters. The other day My Wife got about a half mile from the house and it just started running like this. My first thought is the Catalytic Converter is plugged because of the awful sulfur smell, but before just cutting it out I wanted to look into some other things first just to make sure.

1st I put my old Snap-on Scanner on it and watch cylinders 1 and 2 misfire count just keeps climbing at idle. I increased the RPM and the misfire count started dropping.

2nd I removed the O2 sensor just before the CAT and no change.
3rd I replaced the spark plugs. No Change!

4th I replaced the plug wires. No Change, Kind of worse actually. Won’t start now. I removed the wires 1 by 1 and replaced them as I took them off to make sure I didn’t plug them in wrong.

5th I checked the fuel pressure. Key on reads 60 PSI. Key off it holds 50-52 PSI for over 5 min.

Next I am going to check the cylinder compression. (What should it be?)After that I am not sure what else to do. I heard about replacing the CPI (Central Port Injector) but the fuel system seems to be fine.

Also read about the EGR? (Where is it? and how hard to change). Could it possibly be the timing? Will the chain just skip at some point?

Thank you for the time! Hope you all have a better day then I am having!

most likely Converter

Do your compression test look for very little variation cyl. To cyl. Sounds like it may be running rich and as stated by nhra, may be the cat. Sorry about the caps, to lazy to retype!!

Thanks NHRA and Maxwedge. I'll run the compression test just to rule out. If all is well I will cut CAT out. Do either of you know if the exhaust is stainless? I would like to weld a new CAT in myself but only have a MIG welder.

Yes stainless.