996 4S: Black smoke from the exhaust

[liberatod]

Hello,

I have a 996 4S manufactured by Porsche in October 2004 and in November 2012 I added one liter of Oil Mobil 5W50 and in February 2013 several people told me that my car

had black smoke from the exhaust and smells like burnt. I purchased my car 6 years ago' 2nd hand with 48000Km and now the car has 65000 Km.

On Friday I leaved the 996 at the Porsche garage and after they checked my car they also noticed that the simmering (RMS) must be replaced again (after only 15000 Km).

Anybody knows if the black smoke is a symptom of defective engine that needs to be replaced?

Is it normal that the simmering (RMS) which is the sickness of all 996 needs to be replaced every 10-15000 Km?

I'm lucky because I extended the Porsche warranty every years but this is the last year that Porsche allow me to renew the warranty and after I will have to pay

Due the above I'm very disappointed with the Porsche quality and not sure will buy a new one in the next future...

Liberato

Edited March 10, 2013 by liberatod

[JFP in PA]

Some of the 996's suffered from out of round openings in the case where the RMS sits (Porsche actually developed a tool to check the cases to see if the opening is round or not), which will continue to leak oil after replacing the RMS. Unfortunately, when you find a car with this problem, the out of round condition cannot be fixed, the engine has to be replaced. That said, one of the biggest problems with the new PTFE RMS seal is that people do not know how to correctly install them; they are very susceptible to leaks from something as small as a finger print getting on them, and they should not be installed with any type of sealer (the sealer actually works against the new seal and causes it to leak).

There was a very detailed article on the new seal, installation problems and failure causes in "Excellence" magazine a year or two back. It also showed how to test the case opening and examples of cases that will never seal.

Black smoke is ususally a sign of an over rich mixture, but it is usually not a fatal problem and would also usually throw codes as well.

[JasonStern]

black smoke typically indicates unburnt fuel. are your injectors leaking? is there fuel getting into the oil?

the RMS shouldn't need to be replaced that frequently, but if it was improperly installed or if the shaft is eccentric, that could cause accelerated wear.

edit: wow, JFP is ninja fast at replying. :)

Edited March 10, 2013 by JasonStern

[liberatod]

Hello,

Porsche replaced the engine. The black smoke in particular from the left exhaust was caused from the cilinder #6 dead. The new engine come with a new RMS version and body engine.

[logray]

Thanks for the follow up post. This definitely is in line with what has been reported previously.