05 Legacy 2.5i Burns Multiple Qt's oil

Hello all Subaru lovers alike, I'm new to this forum so I apologize for any mistakes I might make but i have a problem.

 

My 2005 Subaru Legacy 2.5i MT is burning ALOT of oil, I have tried many different oils including heavier weights. My most recent 1100 or so miles look like this.

 

Yes I know my car has 143K on it but it shouldn't burn this much.

 

142483 - Oil Change - Castrol GTX High Mileage, pre-filled the filter, then put the rest in the car till it was full about 4.2-4.3 qts

 

143259

 

Added the rest of the 5Qt jug to the car, about .7-.8 Qt

The dipstick read slightly above low.

 

143529

Added and entire Qt of oil, dip stick now reads full.

 

How has my car used this much oil? No leaks to be found, spark plug wells dry as a bone, muffler has a thin coat of black but nothing concerning and doesn't smoke at all.

 

ANY help is greatly appreciated!

That does sound a bit excessive. My car has always consumed oil, and it consumes more when the weather is warm outside, less when it's cold out. The first thing I would do is try cleaning or replacing the pcv valve. There are some pictures of it in the link below.

 

http://legacygt.com/forums/showpost.php?p=3619336&postcount=50

 

No promises that it will fix anything, but it is a possibility.

I have heard of the PCV causing excessive oil burning so I would definitely check that out.

 

My car burns a lot of oil as well and it started around the time I replaced the headgaskets. A buddy of mine is a Subaru tech for a dealership, and he mentioned that they see that behavior with engines that have been allowed to overheat. The oil rings lose their tension and don't hold back the oil anymore.

Thanks for getting back with me so quickly, my apologies I read apexi's comment yesterday morning before I had to go into work so I went ahead and replaced it.

 

When I pulled it out it had oil on both side of the valve, I did the shake test and it had a little movement but you could tell it wasn't where is should be, so I cleaned it just to see how much movement I could get and there was a little more. I still replaced the hole thing, the new one felt heavier and had a ton more movement too it. Hopefully this will stop this burning and hopefully its not my rings. I would hate to have to do a rebuild.

 

Again, thank both of you for getting back to me, I will let you know how its doing in about a week or so's time!

let us know how it turns out, I'm interested to see if that solves the issue

OP, any updates on PCV replacement fixing the consumption problem?

Replaced my pcv the other day, will let you guys know when/if it changes anything.

 

As a reference, I was burning 1qt/2000mi. So I should see any improvements within the next couple weeks.

1qt every 2000 miles is okay. When I worked for mitsubishi I did many oil consumption tests and most manufacturers go by 1qt per 1k miles.

Probably one or all of these

 

Oil Filter too loose.

Bad PCV

Bad Gaskets or Seals

I'm okay with burning a bit of oil, but I'd rather not burn any if I can help it.

 

Filter was tight/clean when I did the oil.

 

The PCV I replaced was totally useless. I'm guessing that was the source of my consumption, but time will tell.

Make sure you use a metal one not a 3$ plastic one.

Definitely used a quality part. Don't really want to replace it again anytime soon.

Replacing the PCV seems to have fixed it.

 

Almost 1k miles since the fix and oil consumption has gone down to nearly none.