pdxfj

Hello everyone,

My new to me '07 Cayman base showed signs of a failed AOS. Not a big deal to replace.

Well.. I have replaced it twice and the upper vent hose as well. Each time I take the plenum and crossover tube off the intake and clean everything out along with the upper vent hose. Sadly I'm still getting oil in the intake from the drivers side vent hose. The passenger side is dry.

Out of ideas as to what is going on, I took my car to a local indy shop and they did a compression test, vacuum test on the engine and bore scoped the cylinders. No problems found, all tests came back great. My oil level is in the middle of the gauge and the car used no oil on a 1,300 mile road trip I did earlier this month.

Most of the time I get a nice, big cloud of oil smoke on startup that takes about 15-20 seconds to clear up. Mostly happens on cold starts in the morning and cool starts after its been sitting for a number of hours.

Someone I know suggested another shop that are very good with water cooled cars. The shop I went to is well respected, but didn't realize they leaned more towards air cooled.

Anyone have any thoughts as to what is going on before I spend a few hundred dollars more on another shop to try their hand at this? I am not sure if oil is being sucked up though the AOS or pushed up. It's not a major deal, but is rather embarrassing to start your car and have a cloud of oil smoke come out. It's not right and I would like to get this resolved. All of my searches show that replacing the AOS solves the issue,but I have not been able to find anything on this specific problem.

Thanks in advance for any thoughts or ideas you may have.

First pic shows oil in the plenum where the drivers side AOS vent hose attaches. Second pic shows oil in the AOS.