Hello everyone, hope you are having a good day.

My 2000 Corolla, 213,600 miles, automatic, has burning engine oil rate of about 1qt. every 300~400 miles.

It used to worse when I used non synthetic oil before, since I begin to use synthetic blend,it increased little bit of range but still I believe the burning rate isn't that good.

There is clear sign of burning oil than leaking, by watching a lot of white smoke coming out from exhaust in morning and sometime after went to highways with decent high speeds.

I see many solutions by rebuilt engine, change valve seals, or adding some chemical add-ons from auto shop but what you think? I am poor college student, I may not able to have install decent rebuilt engine into my car right now but do you think changing valve seals would help me a lot to solve this burning rate?

I have replaced PCV vlave, wished it was the main problem but it was not.

Please share what you think of this. One of my friend says just keep adding oil as what I've been doing but I think the burning rate wouldn't go better than that so I think replacing valve seals is reasonable investment but I would like to hear what I may don't know about.

Thanks..!

The main cause is clogged piston oil holes behind the rings.

http://www.toyotanation.com/forum/131-8th-generation-1998-2002/402362-diy-oil-consumption-fix.html

You could try an Italian tuneup for now.

http://en.wikipedia.org/wiki/Italian_tuneup

After a good Italian tuneup, add a quart of ATF to your engine oil (once oil level is down to the lower mark on dipstick), let it fast idle for 15 minutes, drain the oil, then run it on high mileage oil... Which state or province are you in?

http://www.walmart.com/ip/Pennzoil-10W-40-High-Mileage-Vehicle-Motor-Oil-5-qt./14962314

Before the Italian tuneup and if you're up to it, you could also remove spark plugs to add about an ounce of ATF in each cylinder and let it soak overnight or longer. Crank engine over before reinstalling spark plugs, with a clean rag over spark plug holes to catch spewed oil and deposits, then reinstall spark plugs... You'd just need to prepare a thin hose about a foot long, secured to a makeshift funnel (squirt bottle cap) with electrical tape, and make sure you don't drop it in the cylinder.