Replacing 997.2 Air Oil Separator AOS
10-26-2016, 10:38 AM
#16
I wasn't sure what to lube the o-rings with so I did a quick search and read somewhere that motor oil wasn't the greatest thing to use and that some manufacturers recommended vegetable oil. Since I had that handy, that's what I used.
09-13-2017, 12:18 PM
#17
Three Wheelin'
Bruce, I wasn't sure what to lube the o-rings with so I did a quick search and read somewhere that motor oil wasn't the greatest thing to use and that some manufacturers recommended vegetable oil. Since I had that handy, that's what I used.
My throttle body was fairly clean on the air filter housing side, but had a good amount of carbon build up and oil on the intake plenum (forward) side. Took some scrubbing with throttle body cleaner and a soft bristled brush to make it shine again. But to be honest, I don't think being a little dirty effects them much. It's probably not until they get so carbon crusty that they stick open too much or can't operate smoothly. I saw no indication of that. But once you get the air cleaner out, you're only 4 quick bolts and an electrical connector away from having the whole TB off so you can clean it. Very easy job. Just don't break a perfectly good part while trying to tidy it up a bit. That's always my fear when tinkering.
I would say all the exess oil I wiped up from inside the intake plenum and each intake manifold probably made up about 1 tsp. I had initially thought that ANY oil in the air intake system was abnormal, but after reading more and more, I realize a small amount is normal. I say "pool" only to differentiate what I saw from a light coating because there was a little more than that sitting on the bottom, but very little. My guess is that if you don't have continuous visible smoke from tailpipes, there's not too much oil in the intake. But I'm no expert.
My throttle body was fairly clean on the air filter housing side, but had a good amount of carbon build up and oil on the intake plenum (forward) side. Took some scrubbing with throttle body cleaner and a soft bristled brush to make it shine again. But to be honest, I don't think being a little dirty effects them much. It's probably not until they get so carbon crusty that they stick open too much or can't operate smoothly. I saw no indication of that. But once you get the air cleaner out, you're only 4 quick bolts and an electrical connector away from having the whole TB off so you can clean it. Very easy job. Just don't break a perfectly good part while trying to tidy it up a bit. That's always my fear when tinkering.
I would say all the exess oil I wiped up from inside the intake plenum and each intake manifold probably made up about 1 tsp. I had initially thought that ANY oil in the air intake system was abnormal, but after reading more and more, I realize a small amount is normal. I say "pool" only to differentiate what I saw from a light coating because there was a little more than that sitting on the bottom, but very little. My guess is that if you don't have continuous visible smoke from tailpipes, there's not too much oil in the intake. But I'm no expert.
03-14-2018, 03:06 PM
#18
Stumbled across this thread. Very nice diy.
is the part number 9A1-107-040-02 same for the 997.2 3.8l? . Easily available for under $100 if you search online.
is the part number 9A1-107-040-02 same for the 997.2 3.8l? . Easily available for under $100 if you search online.
Last edited by Presto; 03-14-2018 at 03:22 PM.
03-14-2018, 11:46 PM
#19
another unsolved mystery on rennlist... the OP's last response was 10-27-2015, think he still owns the car?
03-15-2018, 01:04 AM
#20
This is a aos diy. What is unsolved about it?
03-15-2018, 01:16 AM
#21
I think the unsolved part is whether the AOS fixed anything. I doubt that it did. Haven't seen a case of a verified AOS failure on a 9A1 motor.
Wonder how many miles are on that car now.
Wonder how many miles are on that car now.
03-15-2018, 03:25 PM
#22
OP states "I'm dealing with a flashing CEL and misfires on all cylinders" so he goes on an easter egg hunt for a solution, but we never hear if this "solved" anything.
04-20-2018, 06:30 PM
#23
Rennlist Member
So I'm thinking about changing out my AOS but have a few questions first:
1. Are the 3.6 and 3.8 engines the same procedure, as noted above?
2. I see people mention a 'vacuum' test for the AOS functionality by unscrewing the oil fill cap while the engine is idling. When you do this should there be zero vacuum pressure? Or just not so much that you can't open the cap? When I went to unscrew my oil fill cap with the engine idling, there was a slight vacuum, but once I broke the vacuum I had no issue unscrewing the cap.
Thanks in advance!
1. Are the 3.6 and 3.8 engines the same procedure, as noted above?
2. I see people mention a 'vacuum' test for the AOS functionality by unscrewing the oil fill cap while the engine is idling. When you do this should there be zero vacuum pressure? Or just not so much that you can't open the cap? When I went to unscrew my oil fill cap with the engine idling, there was a slight vacuum, but once I broke the vacuum I had no issue unscrewing the cap.
Thanks in advance!
04-20-2018, 08:55 PM
#24
Rennlist Member
Take it to a shop and they can put a manometer on it to see if it's good or not.
04-20-2018, 08:58 PM
#25
still waiting on the OP answers to AOS question, did it do anything? maybe in 2019
04-20-2018, 09:06 PM
#26
Rennlist Member
02-28-2021, 10:13 PM
#27
Racer
2009 C2S 91K miles
2. Describe "pools of oil" that sounds a bit scary to me
3. I cleaned my throttle body but I did not remove the body itself. I sprayed some cleaner on a rag and got in there as I could with a rag. The thing was BLACK inside but no pooling or anything wet. What was the inside of your throttle body like when you removed it?
Peace,
Bruce in Philly
2. Describe "pools of oil" that sounds a bit scary to me
3. I cleaned my throttle body but I did not remove the body itself. I sprayed some cleaner on a rag and got in there as I could with a rag. The thing was BLACK inside but no pooling or anything wet. What was the inside of your throttle body like when you removed it?
Peace,
Bruce in Philly