Loud Banging noise
 

I hear a very loud, single banging noise coming from an area behind the passenger seat after driving my 2002 Boxter S Tiptronic with 31000 miles a very short distance after the car has been sitting idle for a few days. It only happens when the engine is cold. Otherwise the car seems to perform just fine, i.e., no other weird noises. Anyone else experience this "problem".

Banging you say? You don't hear knocking, do you?

If you're uncertain, have it diagnosed. Good luck.

try to check also your engine mount. I had mine before and during initial drive and at first I thought my tip (newly rebuilt and around 3k since rebuilt only) has low gear issue. After replacing my engine mount, the issue is fixed.