OK I have a theory. It is my theory.....
The tube from the OE air cleaner box that has the extra filter in it is supposed to be connected to something that sucks exhaust gasses or crank case gas or ??? anyway since it was just hanging out there in midair it was sucking a lot of extra air into the air box which was screwing with the air fuel mixture. My sticking that hose in there has restricted it enough that the motor is getting the right amount of air via air intake. IDK whether or not it sucking air from the carbon filter which smells heavily of gas is helping hurting or neutral.