Oil leaking from hose between valve cover breather and turbo inlet.

[SlowSpeedT]

I plan to replace the hose but the oil leak is pretty bad from there. What might cause this? Bad PCV? Bad turbo? Leak coming from valve cover side of the hose.

for additional context: I’ve had this 2012 Mazdaspeed 3 for a few months. All things were fine but I was consuming about half a quart in about 800 miles. The car has 83k miles on it. Mods in include the following:
Corksport Short Ram Intake w CS turbo inlet pipe.
Forge BPV
Auto tech HPFP
Short shifter
Damond rear motor mount
(No tune but have AP to do so once I add a couple more mods)

I decided to change the spark plugs and as suspected the current ones looked terrible. Did find a little oil in the TMIC. Got the new plugs pre-gapped but still measured just in case. Didn’t drive the car just started it up for a few minutes no problem. Next day I went to change transmission fluid and noticed a small puddle of oil. Looked up and saw oil all over motor/rear motor mount etc. upon inspection the highest point I could find oil was where the hose from the turbo inlet connects to the valve cover. I also noticed previous owner zip tied the hose which probably indicated it’s leaked from there previously. That’s about all I have.

 

[Raider]

Got some pressure issues perhaps. What mods do you have?

 

[Cfoldone]

The thread title is not enough to get your answers. Please describe the situation, pictures are great too. History of engine life, modifications listed. Miles, operating condition at time of fault. Full throttle? Full boost? Too full of oil? Low oil, than with oil?
Turbo size, type, engine tune?
Did you look for oil out of front of motor below the intake manifold and will drop and be around oil dip stick/engine block area?
More information will help everyone.
Use the troubleshooting form...to get a list of things to add for information

 

[SlowSpeedT]

Got some pressure issues perhaps. What mods do you have?

i have updated post to include addition context, mods, and pictures.

The thread title is not enough to get your answers. Please describe the situation, pictures are great too. History of engine life, modifications listed. Miles, operating condition at time of fault. Full throttle? Full boost? Too full of oil? Low oil, than with oil?
Turbo size, type, engine tune?
Did you look for oil out of front of motor below the intake manifold and will drop and be around oil dip stick/engine block area?
More information will help everyone.
Use the troubleshooting form...to get a list of things to add for information

updated. Everything stock besides listed mods.

 

[Raider]

Seems like a crankcase pressure issue.

 

[SlowSpeedT]

Seems like a crankcase pressure issue.

I was thinking the same but I’m fairly new to these cars so I wanted a more experienced opinion. I’ll replace PCV and get my OCC installed and hope that’ll fix the issue. Wish I could install the upgraded PCV plate kit from Damond motor sports but I live in California and the PCV is a pain in the ass to have to swap for a smog.

 

[Cfoldone]

To have enough pressure in valve cover and oil, means a high amount of combustion blow by. PVC system helps under vacuum (negative intake pressure which via PVC valve allows crankcase pressure to flow into intake manifold. Once above the PVC valve closure from manifold going towards positive pressure (if it is working!) Then valve cover venting a small amount in a normal working cylinders/pistons/rings from combustion blow by is sucked into intake track.
Photos show long term large oil leaks. No simple way to recover that oil coming out of valve cover breather tube can be fixed by just adding a OCC...
You have to check the health of cylinder/rings apparently they are leaking and getting pressure into crankcase.
Compression test with gage is not enough.
You need to get a leak down test done. That will show cylinder rings and valves not leaking much more than stock ....for a 83k motor.

 

[SlowSpeedT]

To have enough pressure in valve cover and oil, means a high amount of combustion blow by. PVC system helps under vacuum (negative intake pressure which via PVC valve allows crankcase pressure to flow into intake manifold. Once above the PVC valve closure from manifold going towards positive pressure (if it is working!) Then valve cover venting a small amount in a normal working cylinders/pistons/rings from combustion blow by is sucked into intake track.
Photos show long term large oil leaks. No simple way to recover that oil coming out of valve cover breather tube can be fixed by just adding a OCC...
You have to check the health of cylinder/rings apparently they are leaking and getting pressure into crankcase.
Compression test with gage is not enough.
You need to get a leak down test done. That will show cylinder rings and valves not leaking much more than stock ....for a 83k motor.

I see. Well let’s hope I don’t end up needing a rebuild but I’ll see about a leak down test and hope for the best.