Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Reply
 
LinkBack Thread Tools Display Modes
Old 10-25-2013, 03:40 PM   #1
Registered User
 
Join Date: May 2013
Location: Orange County, California
Posts: 266
AOS Oil

Hi guys,

I recently replaced the air oil separator, which I believed to be original. When I replaced it, there was a lot of oil in the intake manifolds. After three months, there has been no smoke or anything, but while troubleshooting the P1128 and P1130 codes, I found a thin film of oil in the intake manifolds, more oil on the rubber boots, and a few drops of oil on the engine below the boots. My question is, if the AOS is working properly, is there supposed to be no oil at all in the intake?

Background info:
2001 Base, 127k miles, has had codes P1128, P1130, P0410, P1411 for a while.
hancock1701 is offline   Reply With Quote
Old 10-25-2013, 04:21 PM   #2
Registered User
 
Join Date: Dec 2009
Location: Toronto, Canada
Posts: 190
When I replaced the AOS I also found that the oil filler tube was leaking. This is sometimes caused by a failing AOS. Excessive vacuum causes the hose to compress and crack.

I think it also caused a vacuum leak because my 1128 and 1130 codes have disappeared since replacing the tube This would only explain the external oil

BTW Its a pain to replace.
brian325is is offline   Reply With Quote
Old 12-18-2013, 05:01 PM   #3
Registered User
 
Join Date: Aug 2009
Location: Dayton, Ohio
Posts: 4
I replaced my AOS after the famous "normal" smoke on start up. I did NOT have a check engine light. I noticed the tube from the AOS to the intake had oil in it. I cleaned it when I changed the AOS. After a few weeks, the "normal" smoking started again. I pulled off the upper tube again and it had as much oil as before. I installed another AOS with the same results. Smoke after a few weeks and oil in the upper tube.

What I learned.. Just because something is called "normal" doesn't make it right. Do I think oil being sucked into the intake is right, no I don't. I went through 3 "good" AOS all with the same symptoms, so I guess it's "normal"

2000 Boxster with 26K. Oil level at full and changed to min with no difference. Oil changed from 0-40w to 15-40w with no differences either.

Hope this was of some help,
Kyle
__________________
2000 Boxster 2.7
Lupdiesel is offline   Reply With Quote
Old 12-18-2013, 07:41 PM   #4
Registered User
 
Tucker2's Avatar
 
Join Date: Nov 2013
Location: Seattle
Posts: 274
Garage
Thanks for this guys. I had an inspection done with a very good Independent after I got my '02 BS. His one comment from listening to the exhaust was he thought the AOS was on its way out.

I ended up taking the throttle body off and yes...there was oil. Not dripping with oil....but a fair amount of oil.

Then I decided to take the throttle body off of my '08 Cayman....and guess what.....EXACTLY the same level of oil.

On both cars there is no excessive vacuum from the oil cap....so I am not replacing the AOS yet on the '02.

I just wish there was a VERY CLEAR description of what the normal level of oil in the throttle body should be. It's been a frustrating thing for me to research.
__________________
Current: 981 Cayman
Former: '02 BS and '08 C
Tucker2 is offline   Reply With Quote
Old 12-19-2013, 10:46 AM   #5
Registered User
 
Join Date: Jan 2013
Location: Phoenix, AZ
Posts: 231
After replacing my "working" original on a '97 with 105K miles I have the same question.

Should there be ANY oil in the vent hose that goes from the AOS to the intake?

By design I would assume the answer is NO, but is there an authoritative source that can confirm this?

If that is the answer, seems a good way of checking the AOS would be to pull the vent line, on the intake side, and look for oil....no?
runjmc2 is offline   Reply With Quote
Old 12-20-2013, 01:48 PM   #6
Registered User
 
Join Date: Aug 2009
Location: Dayton, Ohio
Posts: 4
I believe there should be very little to NO oil passing through the the AOS into the Intake. IMO, I think the factory AOS is to small to handle these engines. Look at the people that install the Motorsports AOS. It's bigger than the factory AOS and I've seen them report a diminish in smoke on start.
I think the AOS is a poor design due to the fact it passes through so much oil from know good units. I think Porsche knows this and just calls it "normal" instead of having fixing the problem. Maybe the Motorsports AOS was a fix. Just think of how much money it would cost Porsche to recall or admit a bad part. Instead it's easier/cheaper for the Porsche dealer to tell you it's "normal".

I'd be courious to see how much, if any, oil passes through the Motorsports AOS..

I worked at a Chevy and Ponitac dealer. When GM didn't have a fix for something yet... tell the customer it's Normal....

__________________
2000 Boxster 2.7
Lupdiesel is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 11:26 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page