my 91 integra has a stalling rough idle problem and its running extremely rich, all 4 plugs are black, compressions test is 180psi per cylinder, no vacum leaks that i can tell, replaced PCV valve, has an intake, runs great when plugs are clean but after about 5 minutes they gum up again, and i have raw gas coming out of the exhaust. Any ideas/suggestions would be greatly appreciated!