TurboTommy

If I take a flashlight and shine it down, the whole filler neck is dry and fine rusty. The dark section you see in the pic is where I just put a bit of oil in a few minutes ago.
I've never seen this before with my previous 951's.
You'd think with the oil mist in the crankcase it would always stay lubed up.

Cory9584

its platic, thats probably just a mix of oil vapor and condensation

ausgeflippt951

...I didn't know plastic could rust...

TurboTommy

Anybody else experienced this?

OriginalSterm

i did, when i had a blown headgasket. the oil/water mixture made a chocolate milk colored residue in the fill neck and on the underside of the cap.

Blackwater

Note to self: Design an Air/Oil/Water Separator (AOWS) for 944/951 application.

Cory9584

a catch can would help you. i used to get some moisture under the cap but now i just get water in my catch can

TurboTommy

My headgasket is fine.
What I've got is dry rust.
When you scrape your finger along the inside of the filler neck, I get a small amount of rusty residue on my finger.
Strange.
On my other previous 951's the inside of the filler was always dark/damp.

reno808

That means u have too drive your car for longer periods of times.

Zuba951

It’s not rust.........That is cooked oil. I have seen a little in my AOWS on my 951. just wipe it out...It forms on the back of my BMW 325Xi oil cap....oil change interval on a BMW per the manual is 15,000 miles..(I don't do that) special synthetic oil...