Advice needed - Smoking Boxster S
 

Last week I took the car out for a spin in a nice autumn evening. After exit highway driving on a country road for few minute I smell something is burning and not sure is from the car of the surrounding as the smell is very light. About a minute or so I was shock when I see white smoke is blowing out from the car in the mirror. It’s really spectacular and looks like a blow engine in F1 race. The car is still run fine and I didn’t notice any noise or shaking from the engine. I parked the car immediately and get tow to the Indy.

I need your advice on what could be the possible cause of this white smoke coming out of the exhaust pipe. My Indy think it could be either a fail oil cooler or crack in the engine. I suppose smoke from exhaust pipe mean either oil or coolant is burning inside the engine. I couldn’t understand how a fail oil cooler could make that happen. As for crack in the engine, am I supposed to hear noise or shaking from the engine? After release some oil the engine produces less smoke now (but still a lot). And still no unusual noise or shaking from the engine.

Any idea on what could be the cause of my problem?

The car is 2001 Boxster S with Tiptronic. Oil change about two months ago. Blow water pipe about a month ago.

Thx for your help.

Search the forums for advice on how to check your AOS (Air/Oil Separator).

When those go bad (diaphragm fails) lots of smoke will be produced.

I strongly suggest that you don't drive the car until it's fixed.

I did search the forum and notice AOS failure could cause smoke. I thought fail AOS would only produce smoke in the cold engine start-up. Seems like it could produce lot of smoke constantly if it fail enough. The car is parked in the shop and I will ask them to change the AOS first to see whether the problem will go away.

Thx

Yes, it's your AOS (air oil seperator).

It's nothing major, but replace it before running the engine again.
Don't let the mechanic screw you. Sounds like he is not familiar with these cars and I would not let him work on it.

I posted a reply previously not sure why it didn't show up.

Thx for the advice. I would definitely change the AOS before I try anything else. As the car has problem on the country side I tow it to the nearest shop instead of the shop I used to. I just worry about whether this guy know how to change the AOS. I read on Youtube seems like a simple task..

This link will take you to a very good explanation of the air-oil separator:

Porsche 911 Air Oil Separator Replacement - 996 (1998-2005) - 997 (2005-2012) - Pelican Parts Technical Article