Driving issues / suspension questions

I haven't been driving my C4S much since I purchased it a few months ago. I did some maintenance and repairs and it's been mostly sitting in the garage. Recently I took it for a spin to finally check it out and here's what happened. The weather was dry but somewhat cold (for LA)), about 50 degrees. I was speeding up the curved ramp to the freeway and felt like the car is almost losing control and sliding out. It was about 50mph at the moment. I got a bit nervous, since I've read before how good this car corners, like it's on rails. Then I got on the freeway, there was some traffic but it was moving good. I sped up and wanted to change lane fast (at around 60-70mph), and again, the car felt like a jelly and like it would lose grip. It scared me a little. I have some HPDE experience on an E36 M3 and even though its RWD it doesn't behave like that. So, my first question: is it tires, suspension or something else? My another issue is clicking sound when riding over speed bumps, potholes etc. My mechanic said that the links (marked red on the picture) are making that sound, since that's more like a track suspension and that's the way it is. I'm attaching pics, maybe someone could let me know if those bilstein shocks are good? What could be done to those links, replaced to something else? I plan tracking this car a few times a year and also use sometimes on the weekends. Thank you.

May be a dumb question. What tire pressure are you running?

What are the date codes on the tires? After a few months sitting, did you check the pressures before driving? 32F 38R

wow, fronts were 38 and rear 44, could that be a problem? I've just adjusted to 32F and 38R, I'm gonna drive tonight and see. I've been in tire shop recently Can someone tell me about this suspension, is it good/bad? Thanks!

Looks like u have bilstien shocks and coils and an aftermarket sway bar. Probably better then stock depending on age. The issue may be that the rest if the rubber in the suspension is near 20yr old. Im guessing something is just worn out.

Just a thought,,, several of the tires commonly available for our cars are fairly bad when the ground temp goes below 45 or so, the compound gets too hard and grip goes away. Also ,, tires as they age can go from great to sucks in a few weeks. Pretty much anything that's a summer / light track tire. Tires want the same environment as a vampire,,, cool and dark. Better yet wrap them. Check all the joints, they shouldn't have any loose to the hand feel, check the upper strut mounts. they get forgotten a lot.. Dont forget to also check the flex joints on the steering shaft to the rack.

Update on this fairly old post... I took the car yesterday to the canyon run for the first time and it was really bad. Same thing happened what I was describing half a year ago. Going into any turn fairly fast ends up in what I think ABS activation? It feels like different wheels are braking themselves in turns. It's so stupid, you can't enjoy the ride at all. And I'm not trying to enter the corner at like 70mph (though it should handle it great I believe), but at 30-40mph ABS is kicking in and yellow triangle with exclamation mark lights up on the dash. Thats definitely not right, I couldn't keep up with a regular sedan in front of me))) Is this a known problem, is there a solution? Thank you.

You just had this car at the track (other post)...did it do it there too? I’m learning that these cars are sensitive to tire pressures, tires and alignment specs.

No, I haven't had this issue at the track at all. But I experienced something like that before in regular driving, that's why I went back to this post.

The loads would have been considerably higher at the track, so you’d logically think you would have felt it there even greater. No other changes to the car between track and road? Same tires, pressures, alignment, temperatures, etc? Traction control on both times? And it was consistent? Not just in one or two corners? (like debris or oil on road)

Is the braking system stock or has anyone upgraded it...things like a gt3 master cylinder. The reason I ask is that I have a friend that did that with his cayman R and after that his abs would be going off randomly making the car squirrelly and wearing his brake pads prematurely. The car was also not as good on the track as stock.

These cars have a fairly robust suspension. What brand of tires are you running, and as asked, how old are they? I like the question about if anything has been done to the master cylinder. When was the last time the brakes were bled? How old are your brake pads? What type of brake pads are you running. Following all these checks (and maybe some replacement parts), might have a shop check the alignment front and rear.

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took the car to my mechanic today, we�ll see what he says. I�ll ask my mechanic, not sure about it. I don�t think it�s stock though. on track I had toyo proxies R888R, my regulars are sumitomos. Same alignment, traction control was ON both at the track and city. during canyon run ABS braking was in pretty much every corner, so it�s not some sand in 1 corner. Tires see above. I put brand new DOT4 braking fluid just before the track event. Brake pads less than a year/1000 mi old, gotta check what kind, but pretty sure some racing kind.

Sounds like the stability control is kicking in, have you tried turning off the abs and the stability if you have it. Then in a safe place do some turns. FWIW these cars reward exact air pressure management.

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For me, this would point to a possible issue with your tires. If it didn�t do it on the track, with much greater loads, but started once you changed tires...well, there is a variable.

My car was scary when I first put on the coilovers and it wasn't aligned or corner balanced. You couldn't tell by looking at it with the naked eye, but apparently the weight was heavily biased on and leaning towards the front right tire. I'd suggest an alignment and corner balancing, provided that the tires are good. Tire pressures affected ride quality moreso than stability in my case.

MiB44: Interested in what your mechanic had to say about suspension, and any additional repairs performed?

The blinking triangle indicates stability control (=PSM) intervention as mentioned above not ABS intervention. The owner's manual describes when and how it works, but don't bother to read it as the meaning is lost in translation (quite funny actually). Contrary to the suggestion to switch it off, I would strongly advise against it as it has proven its intervention was required to keep the car stable and after you switch it off it's all up to you to do so. Are the tyre sizes as Porsche lists them for a 996 4S? If 19" wheels are fitted then what tyre sizes are on them? Correct sizing is critical for both PSM and the AWD (since it's a 4S). Report the DOT date stamps on all 4 tyres as asked before please. Something tells me you haven't look at those yet. Since you have not experienced the behaviour on track with the R888 the cause for the funny driving behaviour will probably lie with your street tyres. To summarize: Mib44 please report back A. Tyre sizes front and rear B. 4 digit DOT date stamp (wwyy) on all 4 tyres