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While changing the air filter, I noticed oil around the intake crossovers. The pictures show this better. Any suggestions on what would cause this?

I'm not burning any oil. In 2000 km, I'm down 1/2 a bar. No smoke on start up. The hose in question, I tightened with another full turn on each of the 4 clamps. But other than that, she's running good.

Am I missing something?
 

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It's common to have oil in the intakes especially if you drive the car hard or track it. And if your car isn't consuming oil you shouldn't worry. If you google air in the intakes you'd find many cars have them. Some due to mods (especially after market oily filters), turbo charging and others due problems with the car.

In your case I see it's mainly oil vapor escaping from the connection. Did you inspect the intake housing and MAF to see if there's oil inside too?

Nevertheless IMHO if your car idles normally, engine doesn't die and doesn't consume oil you shouldn't worry.
 

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Agree with Hassaan--oil in the intake is common when driving a car hard. The last time I pulled my intake plenum there was definitely oil. Keep on top of your oil consumption, but I think you're fine :)
 

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How much oil is normal or acceptable?
I removed the air plenum and I had to put it in a plastic bag because oil (dirty oil) was flowing out (more than a few drops)
I have an AOS on order but still would like to know what is normal
 

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sk8flyer, I've seen a few cars - even mine had a light coat of oil...had to open it to get to the starter. seems that if there is no problem as long as oil consumption or the AOS are ok.

since my AOS was 10 years old I replaced it just in case.
 

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In my case it is not what I would call a light coat.
I had to put the plenum and air intake manifolds in plastic bags to catch the dripping oil.
The MAF sensor is not affected and I cleaned everything install a new AOS and will check in a couple of weeks and after a track day.
The intake on the engine bloc seems very dirty (burnt oil, grime and even grass) and I am a little concerned
I wonder if this is ok or not
 

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The intake on the engine bloc seems very dirty (burnt oil, grime and even grass) and I am a little concerned
I wonder if this is ok or not
Is this inside the intake? Or on the outside? Outside isn't a huge concern unless there is wet oil showing, indicating an oil leak. Inside would be concerning since that's being ingested by the engine, and your air filter is not doing it's job.
 

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Replacing the AOS may help and maybe even solve the problem but if you are tracking the car much it may not be enough
What kind of car is it ?
 

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Radium oil catch can in above is very nice looking quality piece I'm assuming you would need a PCV valve in the line to stop backflow.
It is what the AOS is design to do but doesn't always handle that's why some go to the Motorsport unit for track use.
 

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A bit of oil in the plenum isn't that unusual on these cars, no.

I had some oil in there on my 987.2 to the point where I was getting some dripping onto the top of the engine. Combination of two things:

1) Previous guy hadn't tightened the clamps on the rubber intake runners enough. There's a torque spec in the manual. I tightened them.

2) I noted that if I ran the car at the full mark (not the "overfull" mark, mind you) it would drop to one bar low over time. If I only fill it to one bar below full it doesn't drop as quickly. I assume there's more oil for the OVS to deal with if you keep it at the very top mark and it ends up in your intake. I've started keeping it at one bar below full.
 

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Thanks guy.
It is a daily and drift track car (at least once a month)
Oil was inside the air intake system: from engine block to the MAF sensor hose.

Is drifting could be an issue for the stock AOS?
 

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Definitely throwing the car around is like hard cornering
 

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Yes and also the high revs from drifting. The stock AOS does not hold up well with lots of high revs. Consider moving to the Motorsports AOS.
 

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Unfortunately 9A1 engines are not supported with a MotorSports AOS. LN's recommendation is a deeper 2 Qt sump with a baffle system and running your car with minimum oil in the sump. That means just above the low mark. Not sure about the grass in your induction system, but since you use a PDK, which to my limited knowledge does not downshift for compression instead of using the brakes. This downshift does suck oil if not contained by your AOS (ruptured membrane) backwards to your air filter and covers all in between including the MAF.

Maybe a new AOS is in order for your drifting activities. Do you red line your engine regularly, like 7600 or more?
 

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Your 9A1 987.2 motor uses a different AOS than a 987.1 does. Porsche Motorsports 996/987.1 AOS most likely does not fit on your motor. You might check out this option. Your current AOS most likely has a rupture in the membrane that keeps the vacuum level. I completely overwhelmed my old AOS, until I did it again. Then ordered a Porsche Motorsports 987.1 AOS, which costs much more than the 996 Motorsports version. The other issue is that your DFI engine does not have fuel spraying droplets on your valves, so that oil is also collected around the valve stems and carbonized as well. Here is a picture of issues of DFI 9A1 engines. Using blasting walnut ground up shells is one method to reduce this carbon buildup. Ripping off your heads and completely taking out the valves, polishing the intakes is another. Photo is from google- carbon deposits in 9A1 Porsche 987.2 S engines.

The second image is from a Ford DFI mechanic who does rebuild these heads on a daily basis. Some of the related symptoms are engine knock and sluggish performance. He claims that the spray cans of cleaner injected through the intake system actually causes scratches on the pistons, rings and cylinder walls.
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Why this wasn't an issue with old port injection engines. The intake valves were constantly showered in detergent fuel (if you ran a good top tier brand, or added cleaner on occasion) so the valves could still look like new and deposit free at 100-150-200k plus miles:

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