95 S320 Problem with Trunk Opening
 

I'm still pretty new to this forum, and have learned a lot about maintaining my wife's S320. She loves this car and will NOT get rid of it. I must admit - I like it too! It is a mechanic's dream to work on (I'm a retired mechanical engineer - with lots of time to fiddle with things :))!!

Am having a problem with the opening of the trunk lid - after the car sits for a couple weeks without any movement. Seems that the first time my wife trys to open the trunk - nothing happens for at-least five minutes - after either pushing the inside cabin switch, or pressing the trunk "push-button" release at the rear of the car.

I read previous posts about a defective closing assist pump, and admit that I did replace the large pump that is located under the rear seat about nine years ago - because it failed. But the other pump - located in the trunk above the left side wheel well - is still the original pump. I do not think this pump is defective, since I can manually activate it by closing the trunk latch - with the trunk lid still open. It activates and pulls in the handle in every-time.

What could be causing this problem?

Also, sometimes I do have to slam the lid to allow it to fully close, and retract the lid handle, but NOT always.

Thanks for any help in advance!