Referencing this diagram...

From the near side of the Y-pipe there are two taps. One goes to a blue hose and the other to a yellow/orange one. The yellow/orange one runs to a block tap just above the circled "J."

This appears to me to be a designed-in vacuum leak, since it completely bypasses the throttle assembly and seems to enter the intake area just inside the intake manifold port.

(I noticed this first when I replaced all the vacuum hoses on our '94.)

Can anyone educate me on the purpose of this apparently "desirable" vacuum leak?

Thanks!

 

I am pretty sure there is an extra vacuum line on the auto fd's. So what you are refering to would actually be used on the autos.

 

Nah, he's looking at something else, interesting question though.

 

It is used to help further "atomize" the fuel from the primary injectors when boosting. If you were to remove your lower intake manifold you would see that the port you are referring to feeds 2 small holes, one for each injector.

 

BlueTII,

Thank you. That does make sense.