My 1994 Mercedes E320 wagon was taken to a shop for diagnosis on the high idling issue. The mechanic find out that one of the two vacuum hose nipple (the larger of the two) on the inside and underneath of the upper intake manifold is broken and recommend to replace the intake manifold. That would involve removing air cross over pipe, throttle body removal and resonance valve removal first before getting the intake manifold removal. See the image below.


Notice the green arrow shows two hose nipples. The larger of the two nipples is on the right. The vacuum hose nipple on the right facing you is broken. When I looked at the other end of the hose, it appears the hose is connected to some part below and behind the air compressor? See the image below showing the front engine with the different parts names.


The end hose connection is behind between the power steering pump and the air compressor (betwee number 8 and 9) What is that part name on the end of the hose connection? In addition, the left vacuum hose nipple connected with the hose that goes to the brake booster, I believed.

However, I came across this article that shows another way to fix the vacuum hose nipple without removing air cross over pipe, throttle body, resonance valve removal and the intake manifold. The problem with that is there very limited space to repair the hose nipple under the intake manifold. Here is the article:

Brake booster hose broken @ intake manifold... need help - Mercedes-Benz Forum.

Notice that the article refers to the brake booster hose nipple and not the other nose nipple. Can that type of repair can be done on the right side hose nipple as the article described above?

Does anybody have this issue and if so what was the resolution? Comments and/or feedback is greatly appreciated.

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I would use a plastic glue,and seal old nipple,then use a Y splitter for another vac source.

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Those fittings are part of the PCV system. Basically the fittings are a calibrated restriction between the two hoses. There is an opening in the side of the engine block behind the compressor mounting bracket where the front hose attaches. The smaller hose connects to the metal portion of the intake manifold. Great care must be taken when trying to remove these two hoses from the plastic intake. The only proper repair would be to replace the plastic portion of the intake manifold along with the necessary gaskets and seals.
Do it right the first time then you don't have to worry about doing it a second time.

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Thanks for responding back on the comments/feedback above. I will continue to explore my options in regards to the issue above.

I had the same issue a few years ago. I think I used a plumbing fitting to replace the plastic nipple. I remember it was an easy, quick, cheap fix........

I have a spare manifold if you're interested. Shoot me a PM. It's not a terribly difficult job to remove and reinstall the manifold, and it offers the opportunity to replace all the PCV hoses that are cooked into a hardened state.

Fix a y piece on to the one thats left and block off the broken tube .It would be good if you can get to it, to thread it again as the bits would fall down and out .