Another idle problem

I got a 93 LS with a b16a3 swap…i know you probobly think this is a bouncing idle question…it kinda is but not the usual…when my car is at idle alot of times the RPMs drop from 1000 to 200 to 300 barely running for like 10 to 15 seconds then pick up to normal then sink again…smells like gas really bad when it does it…like just for no reason the timing changes or something…ive changed spark plugs,rotor,cap,fuel filter,throttle body gasket…i dont know what else it could be…a lil help?:shrug:

check teg tips for IACV cleaning