04 Legacy L 5MT burning quart every 100 miles

[kyrien989]

My 2004 Legacy L 5mt is burning excessive amounts of oil. Quart in 100 miles. No leaks. No oil anywhere on motor. Top/bottoms/sides. Coolant doesn’t change nor has had to be topped off not even once since purchased car. 157k. Has upgraded metal head gaskets.

I’ve replaced pcv valve, plugs/wires, started using 15/40w and nothing helps.

Car isn’t overheating. Isn’t losing power. Average 400 miles hwy per tank. 330-350 miles city per tank.

No codes. Not even once has cel came on.

Intermittently bellows a huge cloud then goes away and intermittently bellows.

Compressions all good. Lowest 190. Highest 203.

I’m lost and confused. And don’t want to waste my money on a motor swap if it’s something easy and random I’m missing. Im to the point where I’m about to wrap it around a tree since full coverage.

 

[Ecmbuster]

Explain "intermittently bellows"
2004 Legacy Limited 2.5 L EJ253 or EJ259 engine?
(SOHC or DOHC) non turbo?

https://www.mechanicsdirect.com/fixing-your-subarus-high-oil-consumption/

Why Does My Subaru Use Oil? - All Wheel Drive Auto

Why Does My Subaru Use Oil? For this article I am focusing on oil consumption and not external leaks from the engine, meaning if you check your oil, find it low, it’s not due for an oil change and there are no major visible leaks found with your engine, than this article applies. If […]

allwheeldriveauto.com

Don't bandage the problem with heavy weight oil.

 

[kyrien989]

Non turbo and no idea which engine. How do I tell? And like I can redline it and no smoke. Will be driving cruise set look in mirror and slot of smoke at once enough to cover vehicles behind me then just stops no smoke for 50 miles maybe 10 miles. It’s intermittent. Someone on fb told me “ I guess you could also have a head gasket leak from one of the oil return or fill passages to combustion chamber but that is a rare leak”. I’m lost and might need to pay a subie professional to diagnose

 

[Ecmbuster]

Perform a cylinder leak down test with a professional.