Vacuum connection picture included
 

Hey everyone, I was in the process of checking my boost solenoids and I noticed a line not plugged in... I'm looking for some help to identify these items .. First the line pictured and the black box that sits in front of the upper intake manifold ..Thanks again

are you talking about this circled in red?

Attachment 649011

if so, than I believe you are fine, if you take a look at the stock vacuum hose diagram you will notice there is a empty pipe, I believe mazda put it there because if was maybe supposed to be used for something or maybe they removed something in the pre-production process but just left it there in production...not sure but maybe the gurus here will know why exactly there is an empty pipe there...

Attachment 649012

yup, that is an empty, unused pipe that mazda kept there for whatever reason.

also, to answer you're second question, the black box that sits in front of the UIM is the pressure chamber. it's necessary for the sequential system to work. when the secondary turbo comes online, the solenoid for both the vacuum chamber and pressure chamber opens, and applies both vacuum and pressure to the turbo control actuator so it opens quickly and you get that rush when the secondary turbo comes online.

great thanks guys.... after driving around today and tonight I don't feel the extra rush as describe at 4500... Do you guys happen to have a link to a write up on the UMI removal?

Get a boost gauge first, and just connect it to the unused nipple on the UIM and run it into the cabin through the window or something. We need to see what your actual boost number are. It's much easier to trouble shoot if we know what boost is happening at what rpm.

Ok great ! Will do

this may help with UIM removal :)

FYI this is for the second vacuum tank found on the auto tranny FD!

thanks everyone ! i will get boost gauge and keep everyone updated

like mentioned the empty pipe is used on the automatic cars

UPDATE:
just installed boost gauge... my 1st pull I saw 10 psi without crossover to 8 ... Then the rest of the times while driving I only got 2psi. My Vac was constant at 20