So I've been burning oil lately. It's been getting worse, and not it's affecting idle. Plenty of smoke from the exhaust.

There is also very high crankcase pressure. Oil coming out of the dipstick, and soo much fumes coming out of my breather hose.

I'm thinking: PCV, head gasket, or piston rings. PCV would explain the crankcase pressure, but not the oil burning...

Any way to confirm diagnosis on head gasket vs piston rings?

 

To test oil control rings you can buy a special fitting for an air compressor hose that you can screw into the spark plug socket. Remove the oil cap and run the compressor and if you get any air coming out of the oil cap then you know you have an oil leak.

https://www.harborfreight.com/cylind...ter-62595.html

Eric the Car guy has a video on YouTube where he does this on an '07 Tahoe.

If you have high crankcase pressure then I'd definitely fix the PCV first.

 

To check head vs rings just squirt some motor oil in the low compression cylinder. If compression rises significantly after the oil is added, then it's the rings during a compression test.

Of course you need a non-oiled compression reading or readings to compare to.