cruise control vacum hose

I have a 95 XJS V12 and the vacum hose is off of the cruise control. It appears to be about 30 inches in length. I cannot find the connection it goes to. The car also sounds horrible after start up but clears out after about 30 sec. I did not have this noise when the cruise was working so I hope it is related. After hearing the noise for the first time I found the fan clutch was bad but after replacing it I still have the noise. I hope the cruise control vacumn will slove my problem