i am puttin a 68mm gude throttlebody on my blox intake mani, well it has a iacv on it, so i blocked it off with a plastic plate i made. when car started it has a loopy iacv problem, but its not hooked up.i tried all diffrent combos. using the iacv,not using it and i still get the same problem even though i adjusted the iacv in to fix it. but when i put my old t/b on it stops. someone told me the t/b might have a vaccum leak somewhere?? let me know anythng please, thnx

 

please someone let me know what may be wrong with this, people keep telling me it has a vacuum leak in it, but how can i check to see if it does???