JC3D

So at the track last weekend, I had this weird oil leak that only happened when I jacked the car up from the back middle, and the car was hot. when I lowered the car, it seemed to go away. Never leaked or lost pressure at all while on track, and the leak was minimal.

Not sure what this might be, but one idea was brought up that it might be the air/oil separator. Some of my cayman friends have had to replace them with an upgraded one (996 107 926 00) and said this is what solved their problem.

Is this a similar issue for the 996? The car is tracked a lot and now becoming a dedicated race car. Any thoughts?

redridge

If the car is smoking (really bad)... a sign that the aos is bad. Where is the oil leak dripping from?

JC3D

We can't tell, it may be up top, bu it is dripping down on the right side almost directly above the where the exhaust pipe bends. Nothing on the bottom of the motor is leaking at all.

The car doesn't smoke at all.

insite

FYI, when my AOS went bad i didn't have any smoke. i DID have a bouncy idle and a leak though.

Down South

I replaced my AOS to fix an oil leak on driver's side of the engine. At first, it was only leaking a spot about 1 1/2 - 2 inches in diameter about every day. It eventually got worse, so I had it repaced. Not a drop since, almost two years ago.

JC3D

So then it is on the driver's side?

StephenB

At the rear where the exhaust pipe bends for the exhaust tips? If so, probably a motor mount.

Doug Donsbach

+1

CosmosC4S

I just replaced a bad AOS a few months back.
Never had oil leak, but lots of smoke and poor idling.

JC3D

How would that cause the Oil to leak?

chris walrod

The motor mounts are fluid filled to dampen engine vibration. When you jacked the car up [by the engine], you compressed the mount and if its leaking or on its way out, so to speak. This may be the oil like substance you noticed. Just a guess.

Tippy

The for sure way to tell if the AOS has a ruptured diaphram is to remove the oil filler cap. If the engine starts to run rough, that is the problem. If it idles NO differently, the AOS is not suspect.

cdodkin

That makes perfect sense - nice catch.

Had a motor mount fail on my VW last month, and that was also oil filled and was cracked and leaking.

I bet that's the OP's issue.

996superfly

These info. are good to know, thanks guys!

Macster

but with Boxster engine if oil tube filler cap removed engine will run a bit rough until engine controller has time to adapt to the added air flow into the engine and after the MAF. But in moments idle should settle down, smooth out.

'course, the roughness returns when the cap is installed as the engine controller has to undo the now overly rich adaptation.

But the undoing doesn't take much time... just moments, a minute or less time based on my experience.

Now if the engine didn't react to the removal of the cap that might indicate AOS bad as removing the cap would not result in any significant increase in air flow into engine since the AOS is letting in all the air it can.

Sincerely,

Macster.