85' 2wd pickup gone crazy

[bigboy06]

I am new to the site
my pickup has seen better days
one of my problems is that am burning at least a quart of oil a week or more no leaks

I also have had a problem ever since I took the intake off to fix my air leak. when my truck idles it rev real high an drops down and spits black stuff from the tailpipe(not smoke)

and also when i get below half a tank of gas my truck runs slow if you take off fast it drops down as if you were going really fast in first and let of the gas and when the tank is full it runs like a bat out of hell