checkengineLite cameOn.blown smokeout exhaust.CodePO446 What Exactly is Problem? on 2001 Toyota Avalon

just bought used 2001Avalon.havent had2wks&check engine lite came on.Reads Code PO446!its blowin alot grey/blue smoke,but only when car has set for 3-4hours.changed oil Sunday-still same problems.In fact,had to add a qt oil this morning. Need detailed advice Please

by in Naples, TX on August 31, 2012
2 answers 3 comments
ANSWER by on August 31, 2012
HOW MANY MILES ON CAR. OR (SHOWING ON ODOMETER)? IT IS A QT. LOW OFF OIL NOW AND IT WAS FULL SUNDAY? DOES IT SMOKE ALL THE TIME OR JUST AT START UP THEN CLEAR UP?
COMMENT by on August 31, 2012
140,000miles complete oil change on Sunday-then this morning was quart low.No oil leak ANYWHERE! Only smokes @startup! Any dvice/info greatly appreciated.
COMMENT by on August 31, 2012
ARE YOU SURE IT WAS FULL OF OIL SUNDAY? MOST LIKELY VALVE SEALS LEAKING OIL INTO CYLINDERS AFTER SHUT DOWN BUT THAT IS A BIT EXCESSIVE FOR VALVE SEALS ARE YOU SURE NO LEAKS? NO SMOKE WHEN DRIVING DOWN THE ROAD HAVE SOMEONE FOLLOW YOU TO SEE!
COMMENT by on September 03, 2012
140k on odometer yes we keep checking oil daily because dont wont to get hot and ruin the engine, we also keep adding coolant fluid to the reserve when we add oil so the car is loosing both with no signs except coming out of tailpipe.smokes only at startup or if it has sat there a few hours it might smoke lightly again. but had someone follow me and nothing comes out while driving down road the car only reads code po446 not sure what to do plese help
ANSWER by on April 29, 2013
I have a 1998 Avalon w 260K mi. It was burning oil, blowing blue smoke and smelling awful. I aspirated two 16 oz bottles of "Sea Foam" petroleum distillate through the air intake. This cleans the carbon deposits out of the many valves. This also creates a helluva smoke storm as its getting rid of the carbon deposits, so get ready to drive it down the highway 10 miles to get it all cleaned out. Oil consumption is way down, exhaust is clear and it does not smell. Idle also purrs like a cat now. Check your PCV valve, too. It is inexpensive, but a little engine oil sludge can clog it and cause many problems due to the increase in crankcase pressure that forces oil out valve stems and cover gaskets. Good luck!