Possible bad AOS?

[pmpjuil]

While I was cleaning the engine bay and Throttle body, I noticed one pipe that was covered in what it look to be oil+dirt.

When I looked under the pipe, I could see a small puddle of oil. I do get smoke when I start the car but I don't believe they

are blue. Right now I have 2 CEL codes (P0430: Catalyst Efficiency Below, P0447: Evaporative Emission Control).

Is this oil/white smoke problem related to my CELs? or do I have a two different problem? (One for AOS and One for CELs)

Here are some pictures of the pipe.

Pipe is located at the passenger side.

The Pipe in the middle of this image with a rubbed mark is actually covered in dirt+oil.

Under the pipe there's more oil+dirt.

And it didn't show up on this picture but where there is a leaf.. there is also a small puddle of engine oil.

Edited February 12, 2008 by pmpjuil

[kbrandsma]

The pipe covered in oil is the middle oil fill pipe. I recently replaced mine. When your AOS goes bad it can cause a vacuum in the oil fill tubes (collapse and expand) and eventually crack them. I'm not sure if that is what happened in your case. Heres a link to a recent thread on 986forum.

http://986forum.com/forums/showthread.php?t=15127

It looks like you will also need a new mesh sock.

Good luck and keep us posted.

[wbonsell]

Lots of AOS information over on PPBB. A bit of blue smoke on startup (especially when its cold outside) is pretty normal for many of us. AOS failure generally lets loose with a huge amount of smoke. Since you were cleaning the TB, did you notice any oil inside the TB? If so, then more than likely a AOS replacement is called for. Afraid I can't help regarding the codes. Have never experienced one

2000 Guards Red 986

46K.

While I was cleaning the engine bay and Throttle body, I noticed one pipe that was covered in what it look to be oil+dirt.

When I looked under the pipe, I could see a small puddle of oil. I do get smoke when I start the car but I don't believe they

are blue. Right now I have 2 CEL codes (P0430: Catalyst Efficiency Below, P0447: Evaporative Emission Control).

Is this oil/white smoke problem related to my CELs? or do I have a two different problem? (One for AOS and One for CELs)

Here are some pictures of the pipe.

Pipe is located at the passenger side.

The Pipe in the middle of this image with a rubbed mark is actually covered in dirt+oil.

Under the pipe there's more oil+dirt.

And it didn't show up on this picture but where there is a leaf.. there is also a small puddle of engine oil.

[pmpjuil]

I found a very little amount of oil like couple of drops in TB while I was cleaning.

Btw, where is the mesh sock located?

[kbrandsma]

I found a very little amount of oil like couple of drops in TB while I was cleaning.

Btw, where is the mesh sock located?

The mesh sock is normally located between the accordian elbow and the spring clip on the middle oil fill tube. It is usually about 8-12 inches long. I can't tell if it is missing on your first picture or more than likely it is just completely saturated with oil+dirt.

Edited February 12, 2008 by kbrandsma

[pmpjuil]

I found a very little amount of oil like couple of drops in TB while I was cleaning.

Btw, where is the mesh sock located?

The mesh sock is normally located between the accordian elbow and the spring clip on the middle oil fill tub. It is usually about 8-12 inches long. I can't tell if it is missing on your first picture or more than likely it is just completely saturated with oil+dirt.

If I want to correct this problem since it does not sound normal, I should change my AOS, middle oil fill tube, and mesh sock?

Thanks for all the replies.

[kbrandsma]

I found a very little amount of oil like couple of drops in TB while I was cleaning.

Btw, where is the mesh sock located?

The mesh sock is normally located between the accordian elbow and the spring clip on the middle oil fill tub. It is usually about 8-12 inches long. I can't tell if it is missing on your first picture or more than likely it is just completely saturated with oil+dirt.

If I want to correct this problem since it does not sound normal, I should change my AOS, middle oil fill tube, and mesh sock?

Thanks for all the replies.

That sounds about right. Be careful in removing the middle oil tube so you don't break the ears off of the forward tube as well. Make sure the forward tube hasn’t cracked as well, but it is usually strong enough to withstand the pressure. If it is cracked a new forward piece would need to be ordered and installed. Lots of good info on replacing the AOS check out Mike Flocke's site here.

You should also check your j-tube that connects the AOS to the throttle body and see if oil is in that tube. Make sure it is not cracked or damaged as well. You may need to remove it and clean it thoroughly to determine that it is ok. A new AOS may require a new j-tube. Ask the dealer when ordering. I got mine at Sunset, for about AOS $90.00, J-tube $22.00 plus shipping. I have a 98 - 5 speed with 52K on the clock. And they checked my VIN # to determine that I also needed a new J-tube. I would definitely invest in a pair of Craftsman's clamp pliers. The back clamp by the trunk on the middle oil filler tube is tough to get at but not impossible. Since you will be replacing it, once it arrives some people remove it in pieces. (like cutting it at the elbow). They do the same thing with the AOS and the bellows. A new AOS comes with a new bellows and one spring clamp. I would replace the lower clamp with a screw clamp on the bellows. It will be much easier to install

Before the oil filler tube collapses you could have also checked to see if pressure kept you from opening the oil fill cap in the rear trunk. A good sign besides white smoke that your AOS is failing.

Good luck!

[pmpjuil]

Thanks for the detailed reply kbrandsma. I should take a closer look at other pipes near there for cracks. But my oil level gauge is always full so if there is a crack, I'm hoping that it is very small.

Quick question about the oil fill cap checking method though. Check while car is idling right?

[kbrandsma]

Thanks for the detailed reply kbrandsma. I should take a closer look at other pipes near there for cracks. But my oil level gauge is always full so if there is a crack, I'm hoping that it is very small.

Quick question about the oil fill cap checking method though. Check while car is idling right?

In your case I don't think this would be a good test. If the middle tube is damaged there will be no back pressure to test. I don't think it matters if the engine is running or not, you can check it right after you cut the engine. You may see the tube collapse if it is real bad even with the engine running I suppose. I've never seen that however and I am only guessing.

Here is another thread that might be interesting to you. Check the thread here.

Good Luck!

K.Brandsma

98 Porsche

[tommy914]

On my 2000 Boxster S, I just pulled the hose loose that connects the AOS to the air intake. It had some oil in it. So is that the first sign the AOS is bad? or is some oil to be expected?

thanks

Tommy

Edited April 14, 2008 by tommy914

[1schoir]

On my 2000 Boxster S, I just pulled the hose loose that connects the AOS to the air intake. It had some oil in it. So is that the first sign the AOS is bad? or is some oil to be expected?

thanks

Tommy

Tommy:

Oil in that "upper J-tube" is usually an indication that the AOS is on its way out. Check to see if there is any accumulation of oil inside the throttle body (remove the large hose clamp to gain access).

How much mileage on your Boxster S, and has it ever been replaced before?

Regards, Maurice.

[tommy914]

Tommy:

Oil in that "upper J-tube" is usually an indication that the AOS is on its way out. Check to see if there is any accumulation of oil inside the throttle body (remove the large hose clamp to gain access).

How much mileage on your Boxster S, and has it ever been replaced before?

Regards, Maurice.

39,000 miles and it has not been replaced.

Also, the oil filler tube was leaking, which some have suggested indicates AOS problems.

[atta]

While I was cleaning the engine bay and Throttle body, I noticed one pipe that was covered in what it look to be oil+dirt.

The Pipe in the middle of this image with a rubbed mark is actually covered in dirt+oil.

99 2.5 5sp

My oil filler tube looks like this as well. Covered in oil and dirt. Is this normal, or a sign of a leak? Is the oil filler tube a DIY?

Atle

[1schoir]

While I was cleaning the engine bay and Throttle body, I noticed one pipe that was covered in what it look to be oil+dirt.

The Pipe in the middle of this image with a rubbed mark is actually covered in dirt+oil.

99 2.5 5sp

My oil filler tube looks like this as well. Covered in oil and dirt. Is this normal, or a sign of a leak? Is the oil filler tube a DIY?

Atle

Atle:

It should not be covered in oil and dirt.

The oil filler tube is a DIY, but it is a PITA because of the restricted space to access it. The oil filler tube assembly actually comes in three parts, so you should first clean the old one and then see if you can determine which part is leaking, or which connection (where there are pressed together and connected) is leaking.

Do a search here and you will find diagrams and photos of the three parts, along with part numbers.

Regards, Maurice.

[1schoir]

While I was cleaning the engine bay and Throttle body, I noticed one pipe that was covered in what it look to be oil+dirt.

The Pipe in the middle of this image with a rubbed mark is actually covered in dirt+oil.

99 2.5 5sp

My oil filler tube looks like this as well. Covered in oil and dirt. Is this normal, or a sign of a leak? Is the oil filler tube a DIY?

Atle

Atle:

Here is a thread on the oil filler tube: http://www.renntech.org/forums/index.php?s...ic=19046&hl

Regards, Maurice.