I am continuing to search for oil consumption related posts. I burn about a quart every 500 miles; no visible smoke, no leaks and I foul plug 4 each
5000 miles or so. My consumption rate points to the valve guide seals. The problem is not common, but not infrequent either. How could Toyota continue to use these same seals over so many years of production? The fix is moderately expensive, and most just live with the oil consumption. It leaves the tail pipe black, and leaves a black soot on the back bumper. In this age of clean exhaust, and 95 standards are pretty clean, why didn't Toyota change this with the 90 or 91 production? And it continues on the same motor thru 97.