Here’s something weird. Bought a 2001 996 a year ago. The front suspension always made a metallic noise on uneven roads. A fast klack klack klack. No noise on even roads. Thought, well might be the springs. Bought a new set of Eibachs, put them in hoping it solves the problem. But the noise is still there. Went to the European Auto shop here in Vegas, they checked and checked but couldn’t find anything wrong. Put new cushion on the top of the springs, didn’t help. Anyone out there that has or had the same issue. Weird is that 2 mechanics looked, but couldn’t find anything wrong.

 

It's probably one of two things. The first thing to check is the sway bar/strut mount. The end of the sway bar link goes through the upright and secures the strut. Make sure that nut is good and tight.

The second thing to check is to take off the upper strut mount completely and see if the rubber is ripped out around the center.

Both of these make similar clanking/rattling noises and they are pretty common issues.

 

I'm almost certain that the sound is from your sway bar links.

 

I have the same issue, and also thought that a switch in components would help: actually made it worse with Bilstein HD's and euro (lower) springs. So, we replaced the steering rack, which had some play in it; no better This sound is absent on the road but loud when cruising thru a parking lot with small cracks and bumps in the asphalt. It sounds like it is at the top of the struts but I am thinking that it might be the sway bar. Does anybody know how easy it is to get to the front sway bar?

These cars rattle alot but this is annoying

 

The sway bar is held in place with 2 bolts per side. Very easy to get to with the car 18" off the ground. The connection to the drop links are at the same level. The top of the drop links are higher up and would require the removal of the wheel for easier access. Check the sway bushings when the bar is removed as well as both ends of the drop links. Whilst you are under there, check the inner and outer tie rods for excessive play or stiffness, does your steering make more noise after driving for a while?.
James Greer

 

thx for the reply;

my front end does make more noise (which I would describe as loose bolts after driving very slowly over small bumps/cracks for awhile...? This noise seems high, maybe at the level of the strut towers, which i am beginning to suspect may be worn...we tightened these without effect

The only thing I have seen while under the car is a torn left CV boot (with plenty of grease still inside) I am thinking about calling my mechanic and asking him to service the CV's and replace the strut tower mounts

I daily drive and track the car, and will probably never sell it, but it would be rejected by anybody on a test drive at slow speeds

 

sounds like you have experienced this; i was wondering why my mechanic didn't notice the strut tower mount wear if it was present, is it easy to miss? ps how many miles on your car? mine has about 120,000, the noise started at about 90,000

 

forgot to mention, my car is a 996 turbo, but should be fairly similar up front to a C4

 

Took me a bit to figure out my rattle too.
Found a bad rt. upper strut mount. Replaced the whole shooting match with PSS10's and some mode camber plates and spring perches. Perfect now.

 

gracias, did your axles check out ok? I think its pretty strange that the car does not do this until driven for a few minutes, any thoughts?

 

I had the same issue that had used to happen after a few minutes driving.
From a conclusion, that was tie lods.

The reasons why I said tie lods is that I changed inner and outer,
So I can't indicate which were wrong but noise has gone.

I think removed tie lods was seemed to be normal and this is why many engineers couldn't find the cause.