94 b230ft

I replaced the breather box and plastic Y today to eliminate what I thought was a leaky breather box causing a high idle.
I replaced the small line to the intake manifold a few days ago.

I still have a high idle that drops to normal when I clamp off the line from the small side of the breather box's Y.

What else could be leaking? I checked the short tube to the breather box for leaks. It was solid. The only other thing I can think is that the S-line is bent into an oval on one end, or the big(5/8") line that feeds to the turbo intake manifold is leaking where it attaches to the Y above the breather box.

Any ideas?
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1990 740 Turbo, on its way to stock specs, maybe beyond