Help me diagnose my oil leak

[lunar50]

I noticed a bunch of oil on my vanos pressure canister a while back and was led by you fine folks to change out the vanos gasket and timing chain tensioner seal as possible culprits. Fast forward to this weekend and I noticed more oil on the canister, around the block adjacent to the vanos line, and on the lower part of the block leading backwards. I was going to change the vanos pressure line but decided to look around some more for other clues. I also saw some oil on the drain plug, on the passenger side area where the tranny meets the block, and even some drops on the oil pan bolt that you can see looking into the access holes on the bellhousing (upper bolt not lower). I don't see a ton of oil when I look up into the bellhousing and the cpv is bone dry. The car is tilted up on front jack stands only.

I am still guessing the vanos line or vanos gasket may be still leaking so I am going to change the line. The leak further back and along the oil pan is confusing. Could it be just one big oil pan leak and now that the car is tilted back on jack stands some oil is leaking out of the back and showing on the upper bolt? Or is this a rear main seal leak? I am letting it just sit a day or two to see if it continues to show some drops. I figure it must be the oil pan if it is just seeping sitting still like that. Any guesses?

[FBloggs]

Sounds like a leak at the front of the head(vanos,vanos oil supply, cam cover gasket) and possibly the CPV near cylinder #6 Exhaust side.

[lunar50]

Im hoping most of it is from a vanos line but the oil on the bolt up in the bellhousing is the question

[lemoose]

Leaks drip down and to the rear. Your best bet is changing out the accumulator line for now

[mrgizmo04]

Get some paper towels and start dabbing around to trace. Could be exhaust cam sensor seal, could be valve cover gasket half moons, could be valve cover rubber grommets, could be spark plug tube seals, could be rear main.

After a hard and hot day at the track (110+ ambient) I had a leak down the block around cyl 2/3. I don't run the beauty cover, so it was easy to see but a few of my valve cover grommets and spark plug tube seals were leaking.

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[sapote]

I noticed a bunch of oil on my vanos pressure canister a while back and was led by you fine folks to change out the vanos gasket and timing chain tensioner seal as possible culprits. Fast forward to this weekend and I noticed more oil on the canister, around the block adjacent to the vanos line, and on the lower part of the block leading backwards.

It's called VANOS accumulator (canister).
Possible sources:
Chain tensioner aluminum washer again (did you torque it properly?)
VANOS solenoid block seal leaking (check the block bolts looseness)
cracked VANOS oil hose/line
Top right hand chain guide aluminum/copper washer (on front of the head)

Oil leak from here would be blew by wind and trailed to the rear, making it looks like rear crank seal leaking.

[Arith2]

A few people have had a leaking front main seal recently. Check behind the crank pulley if it's all the way to the front of the block.

[Phoenix///M3]

I just did the vanos oil line and there's a thread on here entitled oil leak. I can tell you that a leak there will throw oil everywhere on the passenger side of the engine and drip down to the pan, etc. That small line is under very high pressure and, being a hard line, is flexing minutely with the engine at the support bracket bolted to the engine. I found the bracket broken and a small pin hole right there were the line had fatigued. I used the Rouge Engineering vanos line from ECS. Make sure to use the supplied crush washers on the top & bottom of each banjo bolt connection or you'll get another leak.

I also addressed all the original cooling system components while i was there as well as belts, tensioners and alternator.

Here's a pic of my stock vanos line with the heat sheathing removed. The hole where the bracket broke was only visible after bending the line back and forth a few times.

[jpiazzam3]

Check the freeze plug under the vanos with a mirror mine blew out and shot oil everywhere