Trouble shooting wizards, you're my only hope (clunking noise + bonus dash lights)

Hello All I'm flummoxed and could use some help from the 996 wizards. 😬🧙🏻‍♂️ Background: I've had a prominent clunking noise in my MY00 996 C2 coupe 6spd front end since purchase in fall '24. I bought the car knowing the original front struts were failing, so I wrongly assumed this was a suspension sound. It's felt in the brake pedal and steering wheel consistently. To date I've refreshed: � Struts x4 � Springs (Eibach lowering) � Lower control arms x4 � Drop links x4 � Bellows, bump stops, bearings, hats x4 � Sway bar bushings x4 � Tires x4 � Alignment x2 (aligns perfectly) Video of clunk: You Tube The noise is still present, but tonight it became a bigger problem. I noticed at speed (only at 45mph+) I can rapidly turn the steering wheel L to R and produce a metal binding noise and feeling that *seems* to come directly from the steering column. As said this also makes its way to the brake pedal. It feels as if there is sudden reduced pedal travel or vibration, that's the best way I can describe it. On the third try during this road test I did this again while pressing the brake pedal. This triggered the PSM and ABS lights immediately, and to me going from nuisance to safety concern. Maybe my paranoia, steering is feeling a bit unsettled now. I've had my indy and Porsche Gaudin Classic look at this and neither can isolate the problem. This has included retorquing everything, and plenty of checking this and that. I even thought maybe a spring was not seated properly. From researching old RL threads, it's sounding like my steering rack may be going, or the ' u-joint shaft .' @Nickshu you made a helpful video in that thread that sounds very similar to what I am dealing with, any thoughts on my noise in the vid below? I asked this last year on Reddit and one of the responses from a TT owner was to check the steering rack, as their car experienced this as well. My other thoughts were wheel bearings or tie rods, but they really seem fine. No play when in the air. Getting under the car the rack did look like it may have had a small fluid leak, but I've never found a drop of anything under the floor. I know it's also possible the clunking noise and brake/steering issues are not related, but that seems unlikely to me at this point. Really appreciate the help from my fellow 911 nuts. Below are photos of my steering rack and u-joint. As always Bradley

I would remove and inspect the tuning forks for play.

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They�re new, replaced with the LCAs.

To actually check wheel bearings you'd need to remove the brake pads and unscrew the axle nut. That said groaning or grinding while driving and turning one direction and not the other is almost always a bad wheel bearing. If the sound changes when the brakes are gently applied that confirms wheel bearing is bad. Could also be a bent wheel hub.

I would think that triggering the abs/psm is related to wheel speed sensors - and not related to your �clunk� (ie: triggering the abs/psm by stepping on the brakes while moving through a turn may not be abnormal�). Sorry I can�t help with the clunk� OBI-WAN KENOBI perhaps?

With the car at a standstill and engine off, turn the steering wheel back and forth and listen. If you hear or feel a thump or knocking rocking the steering wheel back and forth, it is the steering rack or tie rods. Had the same symptoms on my other car. Had to replace the steering rack. It had a lot of slop side to side. And if it is the steering rack, replace with new, not a rebuild. Very expensive...

To check the play in the inner steering ball joints, you must at least remove the outer tie rod ends and the entire boot. Mine seemed to be in good condition, but I had a clunking noise when reversing. Once removed, the ball joints no longer held anything in place. After replacing them, all the clunking disappeared.Before replacing the very expensive steering rack, you should try replacing the inner and outer ball joints; in any case, they will need replacing if you opt for a new steering rack. One last thing: between the steering column and the steering rack, there's a lower steering column arm. Sometimes it's not tightened enough onto the rack and can cause a little play. This arm can also cause problems if its boot isn't lubricated. On Wranglers, for example, this is a very common cause of clunking noises in the footwells.

Open front trunk. Check that spare tire is very tightly mounted.

Appreciate all the replies. 💯 Going back to indy tomorrow ideally. ​​​ @lorenzo974 I've also been reading up on that steering column arm (u-joint?) and currently leaning towards this being the issue vs the rack. Good to know it could just be a loose connection or lubrication. As @dporto suggested it could very well be a speed sensor throwing the codes. @allcool Thank you, yes I double checked this the last time you suggested it, for the very same noise in fact. Also pulled everything out and drove around, still there. Probably should throw new I/O tie rods on anyway. Bradley

I have a similar noise, although not as profound. Curious, does the noise appear always, or only after driving for 15 or 20 minutes - mine is silent until it warms up after 15 or 20 minutes. Even hard to diagnose.

In my case, a clunk/crash that progressively got worse with warm-up/heat was the inner tie rods. Once I disconnected the ball joint from wheel carrier, you could see how loose it was.

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My noise is always there. My front strut bearings where like that before I replaced them, once at operating temp the grinding they produced was very unpleasant. What was your mileage when you replaced your tie rods? My indy checked everything not long ago and didn't find the inners to be lose, but maybe my inners are failing.

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That is very good insight and makes sense.

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Bradley, did you ever figure out where the noise was originating from?

Yes...the suspense is killing the community!

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Visited my indy as planned and went for a road test. He's adamant what I'm feeling in the steering is the PSM grabbing for grip. Talking with another friend here about the front clunking noise got me wondering... could it be the front bump stops? I really struggled with whether the Bilstein B8s came with internal stops or not, and it was only from the help of RL that the answer seemed to be no. So I fitted new stops F&R when I installed the struts last spring. I also saw in FCP Euro's install video below at 13:21 the B8s he pulls out clearly have bump stops. If the bump stops are not supposed to be there, the only other thing I could think are the tie rods. 😬 Bradley You Tube

The bump stops are supposed to be there. Your quickly turning the steering wheel left to right can certainly trigger PSM (braking inside corner wheel to reduce understeer) and from the description of what you notice, it could indeed be that. Having said that, any and each PSM intervention is accompanied by the yellow warning triangle with exclamation mark flashing. Not flashing but it lights up when key at 'ignition on' position? Then not a PSM intervention.

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Thank you for the confirmation 👍 I only had the yellow warning triangle once (the time I grabbed the photo in my top post). It stayed on until I cycled the key, then it was gone. Haven't had it since. Really sounds like everything on that end is fine then. My indy mentioned it could be a body rivet somewhere that had come loose over time (I'm paraphrasing but I recall reading a similar problem in the air cooled section). So still leaning tie rods. I even considered the noise could be the hood struts, is that even possible? PO's records show he changed them fall '22. Bradley

An update on my unresolved noise. During last months oil change my indy pointed out a little play in both front wheels while on the lift. I had never noticed it, so either this is a new development or I never had enough leverage to replicate it when on the ground. I am noticing a vibration at freeway speed. He suggested tie rods, so here's hoping that resolves the noise! Before I order, I want to confirm I have the right tie rods in my cart for my specific rack. We know at some point Porsche used the 99634701105 which seems to be the only one that had a 'ribbed' housing. The 99634701111, 99634701106, 99634701107 racks seem to all be smooth, and in my photo above that's what I have. Can anyone verify? When I was last under the front end I managed to miss part number. Ending in 05? Ending in 06, 07, 11? Thank You Bradley

Another thing to check for the clunk is the exhaust system. Rusted out bolts could cause a similar noise.

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Well, it was about time�replace the two inner tie rods, the two outer tie rod ends, the two boots, and the four clamps.

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For sure. Its inevitable that they will wear out after 25 years and cause a clunking noise. Same with shock mounts and control arms.

May have just had an 'ah hah' moment in diagnosing my front noise. I was looking around the internet and realized I still have my original spring isolators in my front struts. I'm not sure how but I didn't replace these when everything was fitted last year. Mine look very thin and aren't sitting straight between the spring/mounts. Is it possible they are dried out and in need of replacing? I could see this being the cause of my noise and strange rebound feeling in my steering (like a coiled spring reseating itself under load). Mine: Pelican Parts Diagram (F):