Maybe a silly question...only had my car for 2 days. When I cut the engine, about 1-2 seconds later (not even enough time to unbuckle and open the drivers door) there is a thunk. I haven't isolated where it comes from. Each time it has happened I thought a another car door was being closed in my driveway...so it seems to localize behind me. What the heck?

 

When this happens, had you been driving in quiet mode? It could be the muffler valves slamming open after the car is shut down and vacuum is lost. Those valves are always open when you start the car, and close within seconds if in quiet mode when the vacuum builds back up..

 

That could be what it is. I did have the active exhaust off. I wouldn't have expected such a low frequency thump however. It really sounds like a nearby car door closing.

 

I hear it on mine too. I usually am in dynamic mode with active exhaust on. Mine sounds like it is coming from under hood...

 

You had the gear shifter in S (pushed left). When you turn the car off, it automatically goes in P, and the gear shifter physically moves back to its normal position, the spring action makes the sound when you don't have a hand on it.

 

definitely not the case for my instance

 

I don't think it's any cause for alarm. You will notice the car makes all kinds of funny noises on shutdown depending on what mode you are in and what's running when you turn it off. Exhaust valves and vacuum pumps the most common, but normal.

 

I have the same thunking sound from the back of the car, and my shifter definitely doesn't shift by itself.