Here's the deal,

I have a 91 Z28 with a paxton s/c 8lbs of boost, crane hi6s boost retard, ford svo 24lb injectors, tes headers, flowmaster cat back system, comp cams 1.6 roller rockers and a tps airfoil.
All of the sudden, my car started running a high idle around 1500-1700rpms and coughs and drops down to 900rpms then right back up to 1500 area? Then when i bring the rpms up to 5500 rpms, the exhaust spits out some black wet fuel?? I thought my tps, iac, or O2 sensor was bad so i put a xp2400 on the car but no codes were up? Any help would be GREATLY APPRICAITED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

CRAIGER