Do you know the rattle I mean? Like a bottle is loose in my 996 C4S frunk?
It happens at slow speeds only on rough or cracked pavement.
So, after reading numerous posts, I installed the following new parts: strut mounts, strut mount bearings, bump stops, drop links, Bilstein B6s.
No luck.
But yesterday, while road testing some under dash rattle-proofing, I pulled and pushed hard on the steering wheel. There's really no free play, but I applied pressure. I could make it happen and/or make it worse.
So, I now suspect the tie-rods. Possibly the inners, since I checked the outers pretty well.
I'll have my wife pull on the wheel tonight while I'm underneath to confirm.
What do you think?

 

Mine has a very small rattle when it’s cold, seems to go away when it’s warmer. I never did figure it out though.

 

Mine does it too. I think it might be the control arm bushings. It's annoying but doing my muffler delete last year makes some of those annoying smaller noises harder to hear.

 

If you can change its behavior by putting pressure on the steering wheel, you should focus on the steering column.

 

So, I think dporto may be right.
I had my wife turn the wheel while I checked tie rods, controls arms etc, from underneath. Nothing.
When she pulled or pushed the top of the wheel firmly, we got a little noise that is definitely above to steering shaft u-joint. Somewhere between the wheel and the firewall.
So, tomorrow, I'll pull the steering wheel and hope I see something.

 

Ahh, the muffler delete! Cures a world of ills with these cars, there's nothing wrong with it if you can't hear it!

 

On my '99 C2, new control arms fixed what you describe.

 

It was the inner tie rods on my -98, had the exact same sound (only started to sound after the car got warm so after a couple of miles and only when going slow).
/L

 

Update...
So, I just finished a few days of rattle-finding. With my wife pulling/pushing firmly on the top of my steering wheel, I could hear "clicking". (This gets REALLY annoying while driving slow over rough pavement with normal hand position and pressure.)
I got under the car with the belly pan off and could feel it on the upper steering column, not near down the rack. She could make the noise only pulling forward or back, not side-to-side.
I removed the steering wheel and instrument panel. I tightened every nut and bolt I could reach in the dash. One bolt, connecting the column to the cast cross brace took 1/2 turn! That made me hopeful.
But nothing has changed. It's all back together and my road test was depressing.
It is not temperature dependent. Changing struts, strut mounts, drop links, strut bearings and bump stops have not helped.
What am I overlooking?

 

There was a post awhile back where the guy had a similar problem. It turned out to be the column (which I believe is in two or three sections before it attaches to the steering rack). I don't remember all the details, but I think he sourced a used column from a dismantler for a reasonable amount and fixed his problem... See here: http://www.autoatlanta.com/porsche-p...section=403-05 it's also possible it's the u-joint...

 

Stupid as this may sound, did you check the amplifier and the spare tire/tool kit? When I don't wrap all the parts with the tool kit in a cloth, they rattle at slow speed. The amplifier could pop out at the top part of the brace too.

 

Have the coffin arms ever been replaced? I seem to recall others having the same issue over course pavement at slow speeds and it was the coffin arms.

 

Thanks for the feedback.
The link that dporto sent is illuminating. Thank you. I see a number of possible sources.
Yes, my coffin arms are original. I've beat on them repeatedly from below. The source of the rattle seems more local to the steering column. I wish it was the coffins . Much easier to replace.
I'm clueless about how to remove the column and get at the shaft, but will continue to research.
Please send any tips.

 

Suspension noises can seem to “change direction” as they are transmitted through the chassis. If your coffin arms are original I would suggest you change them. Sway bar end links also can do this.

Unrelated but interesting - my 2003 Discovery II had a bad rear Watts link which is located in the center of the truck near the rear differential but the annoying clunks were felt directly under the driver side floor under the seat.

Keep at it, you’ll find the culprit.

 

Time to check the panel fasteners, under side rears , one missing, one loose, one cracked panel hole on a corner slapping with every bump.