Did Toyota ever fix the 1MZFE "oil gel" (sludge) problem? Ex, did the 2002-04 continue to be susceptible to sludge? I've never owned one. From a sample of one friend's 04 Sienna, I see the 3MZ does not have that problem. But did the 1MZ ever get fixed, or did Toyota produce it for eight years with that flaw?