AOS post-replacement question
#1
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Quick question for the more well-versed in all things M97…
I had the AOS replaced about a year ago… Last month I replaced my air filter and discovered oil in the intake plenum.
After the AOS has been replaced, should that still happen?
I had the AOS replaced about a year ago… Last month I replaced my air filter and discovered oil in the intake plenum.
After the AOS has been replaced, should that still happen?
#2
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@Porschetech3 Can you help with this? FYI, he invented the UAOS, a better option when replacing stock AOS.
The following 2 users liked this post by Optionman1:
Beachproducer (02-17-2024),
Porschetech3 (02-15-2024)
#3
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All engines have a certain amount of blow-by. A good healthy engine will have 12-13 Liters per Minute at idle, and less than 70-80 LPM at full throttle...
Here is a simple easy to do test https://rennlist.com/forums/996-foru...w-by-test.html
Here is a link to a thread I just did 3 days ago with a video from a fellow Cayman owner that shows how to do the test on a Cayman, and also shows he had excessive blow-by ( 170 LPM !! ). He had some bore-score on cyl #6 ...https://rennlist.com/forums/996-foru...-in-point.html
There will always be oiliness in the intake system due to oil vapors, but should NOT be enough to pool oil or to smoke on start-up ( or on the Track in corners).
The OEM AOS doesn't do a good job of separating the oil droplets from the vapor, the UAOS is 4X more efficient at doing that, But if there is too much blow-by ( excess of 100 LPM ), then there is an issue in the engine...
Here is a simple easy to do test https://rennlist.com/forums/996-foru...w-by-test.html
Here is a link to a thread I just did 3 days ago with a video from a fellow Cayman owner that shows how to do the test on a Cayman, and also shows he had excessive blow-by ( 170 LPM !! ). He had some bore-score on cyl #6 ...https://rennlist.com/forums/996-foru...-in-point.html
There will always be oiliness in the intake system due to oil vapors, but should NOT be enough to pool oil or to smoke on start-up ( or on the Track in corners).
The OEM AOS doesn't do a good job of separating the oil droplets from the vapor, the UAOS is 4X more efficient at doing that, But if there is too much blow-by ( excess of 100 LPM ), then there is an issue in the engine...
The following users liked this post:
jchapura (02-15-2024)
The following users liked this post:
Porschetech3 (02-17-2024)