Rear left exhaust water and steam?
 

I noticed yesterday that my rear left exhaust seemed to have steamcoming out of it when the right one didnt at all. Smelt like curry too!?

It was raining very hard at the time I picked it up so though maybe a puddle had splashed to the exhaust and it was just drying off but this morning I looked and there is like a white resedue just inside the tip of the exhaust like it water had evaporated and left a white mess.

Looked under the car in the general area and there is a very light oil around the exhaust and some drop marks that look like they are coming from the water tank.

On closer inspection the water tank also has water around the neck and I'm pretty sure its simply leaking down. The car has a full porsche warranty and it seems as though Either the cap is faulty or something else is going on.

Any thoughts?

Possibly the header tank is leaking but check the blue cap of the coolant tank first because maybe the spring is old/weak and is allowing water to pass when it's pressurised, also the water pump could be finished.

Those are the only things that come to mind!