Oil Leak / PCV Puzzle
 

hello, I'll try and keep this succinct. looking for help on tracking down an issue or two. trying to figure out where the oil is coming from, because its all over, and i can't make sense of what the source issue is. ill get it eventually but i would love some input from (hopefully) more experienced folks.


full album: https://imgur.com/a/nMjv6vW

• 2014 brz, 65k. NA, headers and e85 tune, but in process of installing JRSC kit
• car is tracked a lot. ran find last season. no noticeable oil consumption. but i changed oil often and an accusump could mask this
• doing Direct injector service
• found the following concerning things

oil was found:

all around the PCV valve area. wettest just below the PCV valve in areas circled (not sure what to call it exactly) oil residue also in areas above PCV where it would not flow "uphill". if its vapor laden blowby gasses escaping from the PCV tubing, perhaps thats explaining the spread?
https://i.imgur.com/3C2lsGI.png


oil residue also found around the breather hose on the top of the intake manifold. i had wiped most of it off here already. it was fairly damp.
https://i.imgur.com/AP7s7Z4.png

oil residue also found on back of intake manifold, and on intake manifold underside as well (not a whole lot here, but noticeable)
https://i.imgur.com/PNvfXnD.png

lots of oil residue inside intake manifold. each port pretty much looked like this. the inner walls are not 'wet' despite looking like droplets but can be wiped off with a rag. the gasket area is definitely wet. how normal is this? certainly does not look ideal - but this is my first time pulling an intake manifold
https://i.imgur.com/fH12D9F.png

POV from throttle body looking inside intake manifold, you can see what appears to be oil splatter pattern as if oil was flowing into manifold from air intake. or maybe coming in from pcv hose and just making an instant U turn to hit the back wall?
https://i.imgur.com/140EZhj.png

breather hose port in the air intake tube from driver front PCV(CCV?) system, showing oil leaking into it, and patterns of it being drawn in
https://i.imgur.com/OUPYYud.png

pics of catch can that was on the car when i bought it (bought the car last year) hose to manifold was slightly kinked but not shut as far as i know. the hose going to PCV valve did not seem like the best connection (hose was cut crooked) never more than a tablespoon of oil in the catch can after several track days and hundreds of miles.
https://i.imgur.com/Fcue5tO.png

all intake ports looked like this pretty much
https://i.imgur.com/1TWZ88T.png



also one direct injector tip was oily


what does it all mean? thanks for any input. i have not done any compression or leakdown tests. until now no reason to even consider one

I'm thinking my crankcase pressures, meaning vacuums, are wonky. I am not sure why there would be oil leaking into the air intake like that unless for some reason that is pulling a strong vacuum, which as far as i know isn't supposed to happen

maybe accusump is causing overfilling and resulting in a lot of extra blow by?

could it be possible that oem pcv valve has failed?

Get a better catch can setup for sure. You've got lots of blow by for some reason. Leak-down seems prudent

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i was considering the radium dual can setup, since apparently i'm getting blow by on the ccv side too. but so far i agree that leak down might be in order...

Get a leak down test before investing another penny.

I think I will. Looking at which adapter to get, our thread diameter is 12mm right?

bump if anybody else has input

Two of the most common oil leaks (which I recently have now) is the Cam plate and Timing Chain cover.

ive read about those, but neither of these leaks could produce oil on top of the block like i have here.

right now my money is on the PCV connection.

hopefully this has been caused by weird crankcase pressures, hypothetically due to the mishimoto catch can. if that isnt it, i then most likely have a really bad blowby problem, and im also looking at doing a leakdown test to try and rule that out.

I have the same oil catch can. Finally emptied it after 2 years and it was 1/3 full.

I'm boosted and haven't seen oil around that area on mine.



Try to do a vacuum test (using a smoke/fog machine). When going boosted, you want to replace that PCV valve with an STI one since stock can't handle it. Mine wasn't seated correctly (by me) because it's a tight area and I couldn't get to it. Took it to a shop and they smoke test it to find it, they had a hard time tightening it as well but got it done.

update, pulled the plugs, and took some pics of the piston heads. 3/4 of the plugs had an oily base, tips look fine as far as i know. all piston heads had this same damp-ish appearance. hoping to hear back from the injector servicer that they were leaking and thus explaining damp piston tops. still haven't done the leakdown yet

https://i.imgur.com/frcMUgH.jpg

https://i.imgur.com/kOFd9p2.jpg

https://i.imgur.com/j1cytaU.jpg

thx for the reply

PCV valve is getting replaced but just oem. the jackson racing kit has an in-line check valve to handle the extra pressures included. so the plan is to just install as they intended. at tuners recommendation

update: replaced the PCV valve, and the brand new valve had a much more freely moving valve inside than the existing one. the new one will move around when simply turning it upside down, the old one has to be forcibly shaken to get movement. i'm not sure if that is significant or not. by comparison, it felt like the old one was gunked up or something. i can't say if it was 'out of spec', but it would surely be more difficult for a pressure difference to actuate it, especially through a catch can. maybe that helps point toward a faulty PCV being my issue. Either way it was interesting to see the difference between mine and a brand new one. figured i'd share that.

for now i'm deleting the catch can and using a new PCV to see how things go. no leakdown or compression yet.

How is it holding up now? And have you installed the SC?

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Any updates ?

Hey, sorry guys for the late replies.

Yes, i installed the supercharger and ran an entire season last year, about 13 track days on the setup. I never 100% conclusively dialed in a reason for my oily issues, and basically assumed it was just the gunked up PCV not allowing oil to travel correctly, and leaking oil out of the catch can intended to go back into the block. and a loose connection on the PCV hose on the back of the manifold, since it was some home depot tubing from prior owner.

2021 season went great! No major issues all season long. And I'm about to start the 2022 season. Fingers crossed I have another issue free season.


As for this issue, i believe its solved. I am getting oil seepage but, as far as i know, only from the junction in the PCV hose that you're required to cut and insert the Jackson Racing check valve into. Oil is seeping from one of those connections, I suspect because that line is under pressure(boost), and although the pinch clamps are quite tight feeling , they are squeezing rubber and i think when everything is hot, the rubber softens, oil thins, oil escapes.

This is slowly seeping down the hose, onto the top of the block into the same areas (roughly) that i had pictured a year ago.

but its nowhere near as damp or nasty as before. but perhaps in time, it would be. So, I have bought some sleeved worm gear clamps, and I intend to clean up the area, clamp the tubing, and see if it continues to leak, and ideally i see the areas i clean stay dry.

I did remove the intake tube of the super charger and observed evidence of oil in the tube from the intake side (driver side) PCV hose that connects to the intake. it was not as pronounced or as 'drippy' as before, in the pics. it looked more like a oily vapor had been there rather than liquid oil running in. this side of the PCV system was rerouted a bit but not changed really. im not sure the cause of this, maybe its because i didnt use the accusump last season.

I have not removed the manifold to see if its as oily as before, although i am very curious - I am going to leave it alone. im doing a lot of other stuff with the car im busy with, and 'if it aint broke dont fix it'. My tuner says I am not getting enough oil into the manifold/cylinders to cause any sort of combustion issues, so I am content to call it a day for now.

I also ran the entire last season without using the accusump, to see if that changed anything. There's certainly less oil around the places I have checked. so perhaps that could be it. I plan to clean and worm clamp as I said and use the accusump again, and see if i notice any issues.


I'm rambling on - but ultimately i have learned that the things I worried about a year ago were messy and worth fixing, but probably not life threatening to the health of the engine. the old PCV did indeed feel gunked so i am glad i replaced that. I have also not performed any compression or leakdown tests. but the car is running strong

I also learned that a small amount of oil can spread around A LOT, surprisingly so, and appear to be a worse issue than it really is.

I did remove the catch can and do not run a catch can.

my blackstone oil reports are good.

i never concluded about the piston heads appearing wet, or the spark plugs. I have not pulled the new plugs to see if they are wet/oily.

Really, pulling the manifold and plugs would tell me a lot. But I am just busy with other stuff, and now i am content to assume that its either A) dry and fine or B) not actually an issue that its a little oily. after all, the pcv system is designed to put oil directly into the intake tract. i really had no reference on how much oil is good or bad - so many of my concerns were just playing it safe.

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