oooooooh that Smell!

My 93' Burb really smells at startup and once it has warmed up it goes away.
fuel pressure regulator?
EGR Valve?

Dead cat lying on the exhaust manifold perhaps???
But seriously...

What kinda smell???

the smell is a real "rich" smell to me, my wife says it smells like rotten eggs

i think that would be the catalylic converter

Replace the O2 sensor first. A bad O2 sensor will cause the rich mixture and rotten egg smell. Disconnect the batt. when replacing so it forgets the old setting. Then start it and let it run to warm idle.

Be sure to replace all the O2 sensors if there are more then one!!!!!!!!!!!!

Could be as many as 4 of 'em...if they don't fix it it's prolly the catalytic converter

For some reason if one of your injectors arent working or if its a TBI and one of them are disconnected the exhaust can smell exactly like a mexican fart. The EGR probably wouldn't make it smell like that unless something is really odd about it. I would say it's the cat though.

ah, by the way, if you want to test and see if it is the cat or not, try using a really intense heater and warm up the converter as much as possible before you start it. Just take the heat plates off and get it as warm as you can, then start it. It will probably smell right away unless your using a NASA rocket to heat it, but if the smell goes away faster than normal it would probably be the converter.