Start by drying off every joint/part with kitchen or loo roll - scrupulously, run if for a bit (keep turbo temps down!) and repeat, paper towels show up the tiniest damp spot.
Also check its not coming from above such as washer lines and dripping on the turbo by coincidence!
"Careful or someone will set the moderators on you. This is Scoobynet, the place where bull and rumour take logic out for a fight and duff him up, and where "fact" is defined as "any old sh*t that gets repeated often enough for people to accept it without question". Metal pinning device struck firmly on the crown there splitpin.
Simon