Bonzo

You obviously don't know what bleach will and won't do. I'm not talking about putting it on your cloth seats. These drains in all my past (and current) cars have all been plastic, and bleach isn't going to harm the plastic, especially watered down. It was recommended by nationally recognized/circulated newspaper car guys, and I'm telling you that on my Tahoe it worked after nothing else did. ZERO ill side affects.

But again, I'm not sure about a Z, and whether it will work or not. I certainly will not worry about hurting anything though, so if this problem does arise it will be the first thing I try.