corolla oil consumption, seems to be common

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.

"Alex" <someone@microsoft.com> wrote in message
news:L%pIf.13096$2O6.10133@newssvr12.news.prodigy.com...[color=blue]
>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.[/color]

Some Toyota engines have hardened valve guide seals that leak. I'm sure
there have been production changes in the seals over the years.
--

Ray O
(correct punctuation to reply)