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Discussion Starter #1
Trying to hook up this used BOV I bought cheap (head in hands- I really need to start valuing my time)

My car has the ABS delete, which uses the vacuum port at the front of the engine (intake) for brake vacuum booster. Normally this port is hooked to the charcoal canister.

So I was looking for a convenient way to hook the BOV up at the back of the engine, at one point I pulled on some lines and something gave (I know bad move), I thought I pulled a line off a tee. As I was rooting around putting it back together I see this port - looks identical to the port at the front of the engine. And its open...I have had some inconsistent idle.

Looking at the vacuum diagram I dont see this port. I have removed the jack thing and the EBPV.

I searched because i think I have seen some posts on the vacuum routing inside the intake manifold. I cant seem to find anything. Also, not seeing in the Service Notes.

When I start the car I think I am hearing a vacuum whistle but I cant nail it down.

Any links to posts or help appreciated.

IMG_2827.JPG
IMG_2826.JPG
 

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Discussion Starter #3
So the hose diagram is wrong, or not clear.

Is this correct?

The vacuum port in the photo (rear intake) provides vacuum to:
  • Fuel Pressure Regulator
  • Green Egg, AKA Crank Case Vent
  • MAP
Seems like I will be short a hose. The Tee would need to be a 4 way?
 

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There should be a line from the green egg to a check valve, then to a the side of the manifold where there's a TEE port, and then that should go up to the fuel pressure regulator.
The MAP is on the rear edge of the intake manifold and is a barb fitting as shown



The MAP must be on it's own rail of the intake btw.


You can see a bit closer here.
The red is the line from the green crankcase breather "EGG" to the check valve. The red then connects to the TEE in the manifold, and then the Blue goes up to the fuel pressure regulator.
The black shiny elbow under the fuel pressure regulator is the MAP connection. The MAP line is a small diameter hard plastic line.
 

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Discussion Starter #6
Yes!

Thank You

OK I have to remove the CC to see that other port.

So for the vacuum for the BOV. I guess I should NOT tee into te MAP vacuum, but instead tee into the line for the FPR and Green Egg.

Agree?
 

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Fuel pressure rises with boost. Those rails see vacuum when the throttle is closed, and boost when the turbo is creating boost.
The MAP is sensitive to fluctuations, hence the small diameter hard plastic MAP sensor line. I would not tap your BOV line into teh MAP rail. You can use the Charcoal canister port line or the FPR line.
 

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Discussion Starter #9
Thanks again Travis.

Wow now I see, did not occur to me that you see boost and vacuum.

Seems like FPR is important. if it does not see a strong boost signal could you potentially lean out?

Those fittings are so loose and flimsy. I see tie wraps on the pics you posted. Is there a thread on "upgrading" the vacuum lines?

I was thinking, close off all the ports except one, run a high quality line to a little aluminum manifold and then high quality lines from the manifold - no cute little elbows and brittle plastic tees.

Or is there some kind of fail safe and the Turbo stops boosting if you get a big vacuum leak.
 

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Discussion Starter #10
Something like this.

It would be really trick if the manifold had a built in higher quality one way valve in the middle so half the ports were vacuum only and half were vac and pressure. Do away with the silly little plastic one way valves that probably melt and /or get hard with heat cycling.
s-l1600.jpg
 
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