I'm about to have to abandon my 2000 Toyota Avalon v6 3.0 (all Avalons have this and only this engine) with 78K miles because I can't get rid of a diagnostic "Cat not ready" message. Everything else passes fine. Car runs fine, rather better after changing the sensors. If I can't pass CA smog, I can't register the car and thus can't legally drive it. I have: changed both upstream 02 sensors. Changed downstream post-CAT) sensor. I have gone through the following reco'ed drive cycle. 1. Make Sure the Engine Light is Off 2. Check if your Vehicle has a...