I have a 2000 lincoln ls 3.9 ltr. And it started missing real bad and I noticed a raw smell like the catalytic converters were going bad, so I had the codes checked and it said misfiring on multiple cylinders. I put new plugs and new coil packs in it and it still misfires. I had the catalytic converters checked and they told me they were fine. I am still concerned with the raw (sulfer) smell. Any help would be greatly appreciated.