I have heard that the oil vapors are beneficial to the engine as they provide lubrication for the intake valve stems and seats, and they won't last as long without it. I have no data, but makes sense to me.

On my om606, I disabled EGR but left the CCV system intact for this reason. The restrictive intake mud that accumulates is a result of the two combining - take away either one, and the accumulation stops.

For plugging the 12 little holes in the intake manifold, the thumb tack is a clever idea, but since the manifold is aluminum, it would be cleaner to TIG them closed. Goo is less preferable, but JB Weld is probably a more reliable goo on a metal substrate than silicone.

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1998 E300 turbodiesel

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