Any leaking vacuum line will have a negative effect on the operation of the turbo waste gate operation.
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Keeping it running is better than buying new

Yes. That line is usually just "T" off one under the hood.
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Post Back. That's whats makes this forum work.

Dear trichard,

Hope you're well. As I've never owned or repaired any turbo-equipped vehicle, I stood aside, presuming others - with such experience - would reply.

As they've not, might I suggest looking at the front of the turbo, whereon there is - according to diagrams in Volvo VADIS, a superseded dealer parts/service database - what seems to be a vacuum hose nipple.

The diagram does not show whether a hose attached to this nipple runs to the instrument cluster or to the intake manifold.

Even so, to simulate an intact hose, I'd put a short length of hose onto that nipple, and then clamp the hose so there's no airflow. I'd guess there'd be no great change in turbo operation.

But, if there is - and if easing the clamp also changes turbo operation - then I think you have an answer, i.e., a leaky vacuum hose will affect turbo operation.

Hope this helps, i.e., that it does not mis-direct you.

Yours faithfully,

Spook