oryansbelt

Hey all,

So I've had a 951 for 8 years now, done all the work on it myself (including 2 clutch jobs on my back on the garage floor) and have been stumped for the better part of 5 years on a noise that I can no longer ignore...

It sounds like a bearing crunching or a weld breaking when I hit hard bumps, come to a hard stop or turn the wheel more than say 15 degrees without letting the car roll too far (has to roll a little). It started on one side, now its on both... now that I've moved to NYC (from SF), its getting noticeably worse with the potholes and crap roads here. Its not a wheel bearing noise, the same noise occurs whether I'm going fast or slow with the exact same tone/loudness. I get one pop at a time, and its easily replicable but only on the road, not on an alignment rack (you have to be rolling pretty much).

In the course of trying to find the solution over the years, I've replaced the top strut mounts/bearings multiple times. I've replaced the lower control arms with rebuilts, replaced the lower control arm swivels (at the rear of the control arms), I put in track tie rods and a rebuilt power steering rack, and I swapped out my yellow Koni Sports for another used pair (and yes I've done the wheel bearings too). I've replaced all the bushings on the sway bar (and its not that kinda noise either, its much more severe than a metal banging noise, you can feel it through the whole car).

Any help is appreciated. At this point, it must be something that I've already replaced. One thing of note, I think there was a heli-coil put in on one of the lower control arm rear mounts (into the body), but everything is very tight. I've gone over all suspension attachments with a torque wrench and everything is tight.

Has anyone ever heard a noise like this from the yellow Konis?

thanks,
-Ryan

pkt1213

That's odd. I was wondering if it was something to do with your sway bar but it sounds like you have hit all the big things. Hopefully someone can help you.

Welcome to Rennlist.

ButtSled

Did you do ball joints with the new lower arms?

FRporscheman

Maybe it is a wheel bearing. Sounds like you've replaced everything else. If you replace the bearings and the noise comes back, it could be a bent stubaxle/spindle.

I hope you find it!

joonas

Do you have "hacksaw" Konis? If you do, check how tight are the bolts that hold konis in the strut. The ones near the balljoints.

cruise98

This is weird! Internet diagnostics of noises, that is a challenge.

I have some random thoughts...

Have you checked the crossmember bolts, the ones attaching it to the frame?

You do not mention what model year you have.

It really sounds like the strut mount or a ball joint to me. The early style strut mounts are not too sporty in my opinion, the KLA mounts may be the best bang for the buck street car mounts, unless you can find some '87 and later mounts in good condition.
Are you sure the lower strut to spindle bolts are tight? I had a popping noise after an alignment and finally traced it to that.

Brake caliper bolts tight?
Motor mounts in good shape?
When you changed the wheel bearings, did you replace the races in the hub? Are they properly adjusted?

Ben951S

Hate to be 'that guy', but with all of the money you saved doing work yourself, maybe it's time you treat yourself and bring it to a specialty place to let them tell you what it is. Where are you located?

oryansbelt

Sorry it took so long to reply to this, I was in China the last 3 weeks!

I figured it out, your post on crossmember bolts was spot-on. They were loose. Soon as I tightened them up, noise dissappeared. A little disconcerting!! I vaguely remember having a heli-coil put in one of those holes, perhaps that was making the noise?

knfeparty

Holy crap. Those 4 bolts hold up the whole weight of the front of the car. If I was you I would call up heli-coil and ask them for a strength quote or get on re-tapping with a bigger bolt.