Hi,
One side appeared to be of a porous ceramic substance, the other has a non-porous membrane over it and appeared to be filled with some sort of gel?
Cleaning it up of the water on the surfaces had no noticeable effect. I have since replaced it with a new plastic one (dealer said the metal one is replaced by plastic one). There was again no change in performance.
I did not have OBDII available at the time this was done. The water will come back the first time you fire up the engine...the condensation from the exhaust has a straight path to each side of the diaphragm. It must not be that bad of a design...they have been using them for years and with no disproportionate amount of problems that I've seen.
...Ed
