hello can someone tell me what this blue hose is an where it goes to. the reason i ask is because i just bought the uprated metering unit from the the car in the pic and i thought that the blue hose had something to do with it as well thanks for any help

 

My guess would've been, that was for water injection.
Too small for a 5th injector.

No reason for having a vacuum take off, the wrong side of the throttle butterfly!

I think!

 

is it not just a sleeve for the the charge carrier sensor wire?

 

As we discussed in PM

And by the way what car is that? Looks very similar to my friends old one