91quattro

My air suspension is working fine. About 3-4 years ago I went through a period where the shocks were starting to leak, and the compressor was cycling frequently... I can remember hearing that relay clicking on and off almost constantly. Finally the leak got so bad the front end dropped and would not come up. Shocks were replaced with Arnotts. At that time I didn't fully understand how the suspension system worked and so I can only speculate that the compressor must have overheated at times from being overworked and the relay contacts may have gotten a little burned...anyway the shocks are good now, and I've since replaced the relay as a preventive measure. The compressor seems to be working fine, but I hear a slight whine when it runs - that may be normal - but it works. Is it worth pulling the compressor and replace the piston ring? The ring is cheap and it's not a big job, but I wonder if it will have any impact on compressor life at this point.

Panelhead

Due to age the seal may be worn. Also check the beads and cylinder wall while apart.
I put a Meissler on another car. It is very easy to hear it running.

Galco

Rebuild isn't difficult and good 1st step. Look for videos from "bagpipping Andy" as he created the replacement ring and has the best DIY vidoes, search and you shall find...

91quattro

Yeah I've watched that video a couple of times and it doesn't seem hard, once the unit is out of the car.