Rattle/Knock

[RayLHarper]

I've had my 350Z for 4 years and during this time it has had a rattle or something sounding more like a knock of a solid loose component on bodywork or another component. It appears to be coming from somewhere high up in front of me, possibly around or near the engine bulkhead. In the early days this drove me mad and I stripped out all of the dashboard and any loose items in front of the driver, along with all removeable items and components from the engine side of the bulkhead without finding anything (it didn't go away during this time). It appears to me to be something hidden inside or perhaps behind body panels, or in a cavity, but I can't locate the exact spot. It isn't any component that is visible and mounted on either side of the bulkhead. Has anyone else had a similar sounding rattle/knock and managed to locate it? All suggestions considered.

[ZMANALEX]

When do you get this knock?

[RayLHarper]

Any bump in the road and anytime when the road is uneven, the road doesn't need to be bad to make it happen.

[ZMANALEX]

Sounds like it may be the ball joint on the compression rod or the ball joint on the suspension upright. 

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