Hoping some one can help with this.... my Evo 8 has had a small oil leak for a little bit now. It leaks maybe 3-4 drops of oil after I drive the car. From what I’ve found It’s coming from the back side of the block. I’ve taken the intake manifold off and inspected the block for any cracks or holes and found none. I found oil on my knock sensor , but knowing that my knock sensor can’t leak, it’s coming from above that, which would be Cylinder 3 I believe. A little background on the car, it’s a built 2.0 with less than 1000miles on it. The block has a fresh Oem head-gasket and a set of arp head-studs (torqued to spec) . The head has been resurfaced a couple times but according to the machine shop and my builder the head is within spec and is okay to use. So my question is what could be causing the oil leak? Since the head has been resurfaced a couple times do I need to go with a thicker head gasket? Do I need a new head lol? Has anyone experienced a similar issue? I’ve done just about everything I can think of. Hopefully I can get some more brains thinking on the subject and find a solution . Thanks

 

Oil pressure switch is back there also.

Usually a bad headgasket wont leak oil....
Check the oil pressure switch with a mirror.
Valve cover
Cam seals.

Can ad oil dye and check with uv light.

 

Also, intake manifold.

 

My guess would be valve cover gasket because the oil return galleys on the 4g63 that surround the perimeter of the block and cylinder head in the headgasket are not pressurized by anything except crankcase pressure.

Just out of curiosity, were the block and head mating area checked for straightness prior to installation with a true straight edge?

 

yes prior to putting everything together, both the block and head were checked for straightness with a straight edge. Everything was flat , nor warping or unevenness

 

ill check those out and see. I have taken the valve cover off a hand full of times to check the torque of the studs etc. Maybe part of the gasket got pinched or something

 

That happend to me me. Pinched that gasket and i swore to myself i did it right and chased a leak i never fixed.