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I have an annoying little oil leak after rebuilding the engine. It's a strange one though, hard to spot where it's coming from.

At my workplace the car is on level ground and it drips out and makes a few tiny puddles over 8 or so hours but very noticeable. Now in my driveway at home I've left it for longer, obviously since I don't live at work and there's pretty much zero leaks.....The only thing is that at home the car is on the slightest angle so the front is higher, if that makes sense.

I'm getting oil over the air con unit. I'm thinking about removing it so I can see where the leak is better. The valve cover gaskets are fine. Oil filter and it's cooler are also very clean and there's no oil on them... the oil pressure sender also seems dry all around it.

I can't figure out where exactly the leak is but anyone have a clue or similar story that can help me out before I remove the A/C?

I would look at VCG... if you didn't put sealant in the corners, its likely leaking out of there. It can be really hard to see, and it very likely won't leak when you're looking at it. I don't know how oil does it, but its a sneaky one. You need to wipe your finger across suspected areas and see where your finger finds clean oil...

I had a cracked valvecover once... that was a paint to diagnose.

Hmm yeah I do remember putting a nice amount of silicon on the rear one but there's definitely some oil leaks on both sides of the engine. Looks a bit wet above the headers and I can smell bunt oil when I drive, so it must be leaking onto my headers.

I tried checking whilst the engine was running to see if it would seep out. I also revved it up at the throttle cable to see if it would cause any leakage but I can't see anything there.

It's annoying I think I will strip the intake manifold off again in a couple of months and change VCG, add loads of silicon, change the oil pan sealant etc. Oil leaks are soooo annoying, more annoying than bad idle problems I reckon!

Keep in mind the torque specs and tightening order. Overtightening the VC bolts can cause the VCG to fold in certain places and not maintain a proper seal. Careful on the silicone sealant also ("loads" of it could get under the VC and into the head).

Regarding silicone, ya there's specific spots that require it not every where. The silicone should skin over then install the VC and I believe you wait like 15 mins before torquing it down. Clean oil is hard to see must be pooling some where when you park in your drive way. Hey, try backing in.