2001 Carrera 3.4 Coolant and AOS?

[Jerry S]

Hi All,

Its been awhile and lots going on but I picked up an older 996 3.4 a couple years ago which has about 100,000 miles and already had a head fixed due to OH and mixing and sent to the guru in the states to do his repair of the head after a confirmed pressure test. This was done and other head was fine, but with repair done about 10,000 miles ago and having also replaced the cooler but NOT the AOS, I HAVE ONLY PUT ON A FEW MILES (1500) and I now have something I just noticed in the coolant reservoir that is not good.

Whats your thoughts? Is there any chance of the AOS leaking between as I know this generation had the oil line to the unit.

[rfuerst911sc]

A manometer is the tool for checking the AOS . Do a Google search for " Porsche manometer readings " or similar and you will finds tons of data . All Porsche DIYers should own a manometer and they can be found for 50 bucks or so . You will have to modify an oil filler cap .

[markp92692]

[tonythetarga]

If you have an oil and coolant mix, it’s not from the AOS. Oil in the AOS goes into the intake and belches blue smoke out if the tailpipe. Intermixes are either cracked heads or a failure in the heat exchanger on top of the engine allowing the two liquids to mix.