FC Drifter

this may be a stupid question but ill ask anyway. theres this little thing on the inside of my t2's lower intake manifold. its in between the fuel injectors. it has two tubes on it for vacuum lines. one tube, the upper tube, is larger than the other, lower, tube. what is it. if i can find a camera ill take i pic. i dont have any vacuum lines going to it, its capped off and i think it may be keeping my car from starting. please help. thanks