White smoke, not AOS issue
05-18-2017 | 04:21 PM
#1
Thread Starter
1st Gear
Joined: May 2017
Posts: 1
Likes: 0
White smoke, not AOS issue
Hi there from SA.
I am new to rennlist, I have gone through quite a few posts hopping to get some head way on the issue I am having. I recently bought my first Porsche, I unfortunately don't have any history on the car. If I push the car over 4500 rpm then I have the AOS pushing oil into the In take cause massive plumes of smoke and the motor runs rough. I immediately replaced the AOS, when doing this I realised the one I was removing was also brand new. The issue unfortunately persisted dispute replacing the AOS. I broke the removed AOS open to make sure that there was some kind of hole in the membrane, and it was in perfect condition. I then disconnect the AOS from the intake and attached a 1liter bottle and drove the car around the block, the moment I go over 4500 it pushes oil into the bottle. I realise that naturally the OAS cannot stop the oil without sufficient suction but I went less than 1 kilometre and had already accumulated 500ml of oil in the bottle. Any suggestions would be greatly appreciated, as long as they aren't replacing the AOS
I am new to rennlist, I have gone through quite a few posts hopping to get some head way on the issue I am having. I recently bought my first Porsche, I unfortunately don't have any history on the car. If I push the car over 4500 rpm then I have the AOS pushing oil into the In take cause massive plumes of smoke and the motor runs rough. I immediately replaced the AOS, when doing this I realised the one I was removing was also brand new. The issue unfortunately persisted dispute replacing the AOS. I broke the removed AOS open to make sure that there was some kind of hole in the membrane, and it was in perfect condition. I then disconnect the AOS from the intake and attached a 1liter bottle and drove the car around the block, the moment I go over 4500 it pushes oil into the bottle. I realise that naturally the OAS cannot stop the oil without sufficient suction but I went less than 1 kilometre and had already accumulated 500ml of oil in the bottle. Any suggestions would be greatly appreciated, as long as they aren't replacing the AOS
05-18-2017 | 05:03 PM
#2
Race Director
Joined: Sep 2006
Posts: 19,032
Likes: 256
From: Centerton, AR
Hi there from SA.
I am new to rennlist, I have gone through quite a few posts hopping to get some head way on the issue I am having. I recently bought my first Porsche, I unfortunately don't have any history on the car. If I push the car over 4500 rpm then I have the AOS pushing oil into the In take cause massive plumes of smoke and the motor runs rough. I immediately replaced the AOS, when doing this I realised the one I was removing was also brand new. The issue unfortunately persisted dispute replacing the AOS. I broke the removed AOS open to make sure that there was some kind of hole in the membrane, and it was in perfect condition. I then disconnect the AOS from the intake and attached a 1liter bottle and drove the car around the block, the moment I go over 4500 it pushes oil into the bottle. I realise that naturally the OAS cannot stop the oil without sufficient suction but I went less than 1 kilometre and had already accumulated 500ml of oil in the bottle. Any suggestions would be greatly appreciated, as long as they aren't replacing the AOS
I am new to rennlist, I have gone through quite a few posts hopping to get some head way on the issue I am having. I recently bought my first Porsche, I unfortunately don't have any history on the car. If I push the car over 4500 rpm then I have the AOS pushing oil into the In take cause massive plumes of smoke and the motor runs rough. I immediately replaced the AOS, when doing this I realised the one I was removing was also brand new. The issue unfortunately persisted dispute replacing the AOS. I broke the removed AOS open to make sure that there was some kind of hole in the membrane, and it was in perfect condition. I then disconnect the AOS from the intake and attached a 1liter bottle and drove the car around the block, the moment I go over 4500 it pushes oil into the bottle. I realise that naturally the OAS cannot stop the oil without sufficient suction but I went less than 1 kilometre and had already accumulated 500ml of oil in the bottle. Any suggestions would be greatly appreciated, as long as they aren't replacing the AOS
Are you sure the oil level is correct? An engine overfilled with oil can route a considerable amount of oil through the crankcase ventilation system that can easily overwhelm an AOS.
On this same line of thought is the coolant level ok and stable? An intermix problem can have coolant in the oil and this can raise the oil level and excessive oil out the crankcase ventilation system can be the result. (Admittedly if this were the case likely you would have noticed coolant in the oil in the bottle. Still you need to eliminate all possible explanations.)
Are you sure the head oil scavenge pumps are installed correctly. These can rather easily be installed wrong and if so can either not scavenge oil as effectively as they would otherwise, or even not at all.
Is the oil pressure reasonable? I mention this because what can happen is the camshaft cover is removed and upon installation is not sealed properly. While the camshaft may not leak oil to the outside it can leak oil -- under pressure -- under the camshaft cover. This puts a tremendous amount of oil there which gets whipped up into a froth by the whirling cams and this froth/vapor then as pressure builds in the crankcase -- due to blowby mainly -- can cause this to flow out of the crankcase and you capture the result.
05-18-2017 | 05:19 PM
#3
Drifting
Joined: Apr 2014
Posts: 2,335
Likes: 25
From: Los Angeles
Can you ask the PO what work was done? Macster has a great point about the oil level. The Cam cover issue - look carefully at the green cam cover plugs- if they are suspiciously new -that may be a clue.
I would also remove the oil filter and change it incase there is anything odd there.Good chance for more forensics also.
See Post #5 here:
http://986forum.com/forums/general-d...nging-oil.html
I would also remove the oil filter and change it incase there is anything odd there.Good chance for more forensics also.
See Post #5 here:
http://986forum.com/forums/general-d...nging-oil.html
10-11-2017 | 06:37 PM
#4
Drifting
Joined: Apr 2014
Posts: 2,335
Likes: 25
From: Los Angeles
Do you have a misfire code?
Does the white smoke only emit when the engine is cold?
If the answer to both the above is "Yes" -be careful -it could be a leaking-open injector overfueling.You may notice the header is wet near the leaking injector. If you run the engine until the cat gets hot you may get flames from the exhaust and you may destroy the Cat.
So do a fault code check for "Misfire"
Then check for spark ,compression and Vacuum at the oil filler cap(less than 5" water) .If all good ,suspect leaking injector(s).
Disconnect the AOS hose and plug(Pelican hack) .That will eliminate AOS from the suspect list
Does the white smoke only emit when the engine is cold?
If the answer to both the above is "Yes" -be careful -it could be a leaking-open injector overfueling.You may notice the header is wet near the leaking injector. If you run the engine until the cat gets hot you may get flames from the exhaust and you may destroy the Cat.
So do a fault code check for "Misfire"
Then check for spark ,compression and Vacuum at the oil filler cap(less than 5" water) .If all good ,suspect leaking injector(s).
Disconnect the AOS hose and plug(Pelican hack) .That will eliminate AOS from the suspect list
Last edited by Schnell Gelb; 10-13-2017 at 09:51 PM.