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Lately I've been trying to diagnose and fix some oil leaks on my evo 9. One is around my oil cooler which I'm already trying to sort out but the one that confuses me is the oil I'm finding on top of the intake manifold. My best guess is its coming from the valve cover but a new gasket was installed a few months back along with the VC (purchased used from someone). I've used some SS bolts to install the VC and I notice when I go check to see if they are still tight, some are a little loose. I went ahead and reinstalled all VC bolts and added some loctite blue to see if that will prevent it from loosening up. I noticed my intake cam shield also has a small leak so I will be buying a new gasket for that tomorrow. The whole point of my post is to gain knowledge if it's possible the oil is coming from somewhere else? Here is a picture of what I'm talking about
This has been a little more oil from what I'm used to. Trying to diagnose and fix these issues on my own has been leading me to a dead end so I hope I can gain some more knowledge from you guys. Thank you
I literally have the exact same question. I have a new vc, gaskets, and am running a saikou michi catch can. I'm thinking it might be crank case pressure. My car blows the dipstick out if I beat in it, so I zip tied it. Gotta come out somewhere, right? Also, I'm running a brand new boomba check valve. Sub'd for answers.
Well assuming all the lines are secured properely, it could be coming from the catch can if its VTA. Could also be coming from your bov if its VTA as well.
1) dip stick, blow by.
2) one line running to the catch can? should be routed back to the intake with a pcv valve.
3) if you looking to limit blow by with the set up you have--there is a thread on here that vents the other side of the vc and drops pressure keeping the dip stick in.
4) as mentioned VTA on the catch can? not good--blow by will be all over when you hit boost
Good luck.
My catch can is the STM one which is VTA. haven't hit boost too hard lately so I've been keeping my spring off my dipstick and also because I'm checking my oil levels frequently. BOV is also VTA. So far I've cleaned it up since I made this post and its staying dry. I feel like it is coming from the VC, but maybe with the crank case pressure it is spewing past the gasket? My engine bay isn't splattered with oil when this happens if that information helps.
Asu, I doubt understand your response. Could you elaborate? The oil on my im is from my bov? I'm lost.
Sometimes excessive crankcase pressure can cause oil to be forced back through the intake system. More common with FP BB turbos but has happened on others. This pretty much coats your intercooler/piping and you can get oil coming from your bov it its VTA.
Oil can go over all over your engine just from oil coming from the bov. Not saying that's your issue but just a possibility.
VC gasket usually just leaks around the valve cover. Doesn't really spray/
