Help with noisy Bilsteins on my '02 C4S

[ntrylvl]

My '02 C4S Coupe has Bilstein PSS9's installed by the previous owner. I bought the car in 2007 with these already installed and only 30K miles on the odo, and have since put just 6K on it myself.

For the last several months, the car has been in and out of my mechanic's shop in an attempt to eradicate various causes of a noisy front suspension. First, the problem was a "creaking" sound caused by broken/deteriorated upper front strut mounts, which my mechanic replaced. That seemed to solve the problem until a couple of months later, when I started to hear a "binding" sound--actually the opposite of binding--would this be called an "unloading" sound? Basically, on certain right turns at slow speed only, I could hear a "knock" in the right front suspension. No similar sound from the left side, and no noises at all under normal driving conditions.

My mechanic was able to duplicate the noise and noted that the inside diameter of the front spring appeared LARGER than the outside diameter of the upper spring retainer, causing movement and the sound. He then had several phone calls with the head tech @ Bilstein, who said he had heard of similar problems, but had no specific fix. Said tech then recommended installing teflon "isolators", which are normally installed in the lower part of the assembly, in the problem area as a potential fix. My mechanic installed these, and the unloading sound did, in fact, go away (has not happened one time since), but now there are creaking sounds and a slightly sloppy feel coming from BOTH sides of my front suspension, again at low speeds or when going in and out of driveways, over speed bumps, etc. Obviously, these sounds must be related to the isolators that were installed.

Has anybody had a similar problem and been able to determine the correct fix? If not, can someone recommend anyone in the SF Bay Area who would likely be able to help?

This is very frustrating. I am tired of taking my car in and out of the shop and I feel like this particular issue is over my mechanic's head. I am concerned that I won't be able to determine a definitive fix.

Thanks in advance for any help/suggestions.

Chris Harrell

Edited November 29, 2009 by ntrylvl

[Daren]

Try Suspension Performance in Mountain View (650)625-8499. I've had Eric Gauthier who owns the business work on several of my cars with excellent results.

[Yoops Racing]

This is a normal occurance on some PSS9s especially on the right side and when the strut is compressed then released. My 99 with PSS9s does this every so often,(also only on the Rt side) usually over a speed hump or exiting from a incline. The spring is binding at the top strut and making the clunking sound. Do a google search on Pss9 sounds/clunking. There supposedly is a kit offerred by Bilstein to fix this. To my knowledge there is no damage just the noise.

[Joel Pirela]

Also try the tie rods on the steering. (inner and outside ones) as they can be a hard to track noise generators...