Gentlemen, I have an S5 TII and it has been running like many of the other cars in this forum section... not well haha. Anyway, the senior members of this forum pointed out to me that it is possibly a vacuum leak, so I went hunting and didnt find any with a spray can of carb cleaner. I did however notice this weird part attached to the side of my lower intake manifold, right below the secondary fuel rail. It had a funny looking split tube on it and bridged between the intake tubes for the primary injectors. I took it off and sprayed cleaner in it and this nasty brown goo came out. At this point I figured it couldnt get any worse if I broke it, so I opened it up. It had a little rubber diaphram in it that was supposed to open and close due to changes in pressure over a threshold, but was 'gooed' open and the diaphram was torn to pieces. This was one of the major sources for my vac leak but I would like to know what to do about this piece. I have looked in FSM and for other pictures on the internet but all I have found is that piece removed and blocked off on the LIM. What is this, what is it for, and should I try to find another one? I'm stumped.

 

you need to post a pic.

 

Sorry, I was out of town for the last week and couldn't post them sooner. If you know what this is, can you tell me if anything is supposed to hook up to it (i.e. vacuum hoses) and where they run to.

The rubber diaphragm in the picture is torn around the plunger and I'm pretty sure that it is only supposed to push open when under positive pressure from turbo boost. This block has a channel in the back side to communicate between the holes from the two primary intake tubes.

Please let me know what I need to do with this thing. My FC runs terribly.

Matt