Odd clunk noise when stopping
 

I have a '99 Boxster with 27k on the clock. Recently a "clunk" noise has developed. I need your help in finding it.

TIMING: It happens when I slow to a stop, and then at the last second, before true-stop, there is a "clunk." It's at that moment when inertia transfers from forward movement (braking) to backward (the stop). It does NOT happen while driving and does NOT happen over bumps, so I don't think it is suspension related.

LOCATION: The sound is coming from what sounds like the passenger door area. Passengers say it is coming from their lower door panel area about the thigh or butt height.

ATTEMPTED EXPLORATION: I have taken the door panel off and driven the car. The noise was still there so NOT in the door panel itself. I have taken the footwell area (above passenger's feet) apart. Nothing seems loose.

Any advice would be appreciated.
Thanks!

Have you looked inside the door? Something might be loose and rolling around.

Windows up or down?

Is it a Tip? If so, does it do in when you come to a stop in neutral?

I have taken the door panel off and reached around inside the door frame as best I could. Nothing seemed loose. Window scissors and air bag seem firm.

Waving door between open and closed produces no sound. Only time there is a sound is when I am rolling to a stop.

Same noise windows up or down.

Manual car.

I feel compelled to suggest the engine and or trans mounts?

Is there something really small rolling around under the passenger seat?

You might also check that the front brake caliper bolts are tight. Also check the pads, are they floating around in the calipers?

+1 on engine or xmission mounts. Also, rear trailing arm connects to the body near the seat. That will clunk as well with a worn bushing. With only 27k mi. in 21 years I'd look for failed suspension rubber.

Any chance it comes from the wheel area? I had a similar experience with new brake pads that moved just so slightly when the car came to a complete stop. You may let someone stand outside and listen, to try to locate it.