My 91 940T has an exhaust leak but I am not sure if it is from the manifold or the flange. I know it is rare to have a flange leak (where the turbo connects to the manifold) but this area has a white coating on it. The loud ticking or "tut tut" sounds like it is coming from the front of the manifold but the white on the flange looks like a good sign it may be coming from there. Studs are stripped on the manifold, so I am kind of hoping it's the flange.

Any opinions? Is the whitish color a sign of a leak or would it still be the manifold and not the flange?

Thanks