4.3 running rough

[73hillbillyk10]

friends 85 k10 tbi 4.3 running rough did tuneup (wires,sparkplugs,cap,roter) but still running rough also smells like its running rich any ideas on what it could be?

 

[EIB8400]

o2 sensor?

 

[BoondocK5]

Vacuum leak?

 

[MTNMIKE]

check catalytic converter? Ever since i had to replace mine on a reeeeaaaalllly long road trip, its the first thing i check!

 

[sloth]

X2

My 4.3 started running like crap last year and had a real rich smell and it turned out that the cat was all clogged up.