I had my motor rebuilt and noticed a barb on the back of the intake manifold. Looks like a hose goes on it, but not sure what. Any ideas?

 

im almost positive that goes back to the carbon canister....


you need to either find the hose thats just laying somewhere, and put it back on...
or cap that.

picture example
https://www.ebay.co.uk/itm/mitsubish...-/263041417982

 

I can't even see what you're talking about lol. But if it's larger than EGR, and in the back, it's for the EVAP system.

 

That T-bolt on the throttle body is going to pop right off with any good boost. It's not even fully on.

 

I don't see anything, either, and +1 on the t-clamp. It's clamped over the lip of the TB and should be behind it.

 

The barb is shown in the middle of the 2nd pic. The first pic shows the general location.

 

Ah. Got it. I'd have to look. I'm not sure LOL

 

Wierd thing is the car drives fine and just passed CA smog . Haven't been able to drive under boost yet since the new motor only has 150 miles on it.

 

The barb takes a black plastic gizmo that supports the three metal pipes.

 

if you look at that picture i posted... you can see that the pipe you are concerned about routes right over to the evap solenoid.

in your current state, if that solenoid opens, then you have a straight vacuum leak to atmosphere.

if that solenoid is closed, you have no leak..

as i said... you need to cap it or find the hose that is laying somewhere and plug it back in

 

Is the evap solenoid directly below the barb? Hard to see with all the stuff under the intake manifold.

 

The smog station must have not done a visual inspection otherwise they would have let you know about it, just the sniffer test. Smog ****'s here are very excited about getting your car off of the road or impounded. The car drives fine until the T-Bolt clamp pops off. I would loosen it up, readjust it back some, and retorque.

As others have said, that open barb behind the intake manifold is for the evap emissions control system. You likely have the evap canister hose just dangling behind your engine not connected to anything. It's a common mistake that non-evo specific shops make. Look for it by following the fuel feed line from the driver side of the car all the way to the hard line. You can ziptie this hose up somewhere for now, but you really should place a cap on the barb fitting as it could cause a vacuum leak. You'll be losing power and efficiency.

 

Not sure if it's directly under it, but there are two solenoids that deal with the evap system. They are both part of the pipes bolted to the back of the intake manifold

 

I found the hose and secured it to the barb .Thanks for the descriptions of where to look for the missing hose . And yes, I re-tightened the t-bolt clamp lol .

 

image is too blurry but looks like it goes to the evap cannister, try follow the hose and feel if it goes to a sort of cylinder shaped plastic can.
also checkout this thread
https://www.evolutionm.net/forums/ev...-canister.html