Rotten Egg Smell
#3
MBWorld Fanatic!
![](https://mbworld.org/forums/images/ranks/veteran_army.png)
#4
MBWorld Fanatic!
#5
MBWorld Fanatic!
Your cat(s) need to be replaced. The easiest way to find out is to take a laser thermometer gun and check surface temps before and after the cats. If one shows a much higher reading post cat that will be the one that's clogged.