catalatic converters?

[verysweepy]

my 93 xlt emits a rich fuel smell sometimes when I start it up and shut it down, could this be my cats going out on me?

 

[aviator]

Check your fuel cap. You should hear pressure release when you take the cap off. If you don't I would think you may have a bad cap or losing pressure somewhere in the fuel system.

 

[Ross-N-Chicago]

91-94s are infamous for our fuel pressure regulators crapping out. Could possibly a bad o2 sensor reading lean.

 

[mattadams]

could be a few different things, it probably is not your cats, but probably either o2 sensors, fuel pressure regulator, problem with an injector or something to that extent.
If you think it is your cats, try and replace em with some free flows... not sure what is available specifically for your explorer, but I have emico's on my F-150, and I'm sure they could be made to work on the Explorers.