cyberay

The sooty condition could be simply an oxygen sensor that needs replacement. They are located in the exhaust system leading away from each manifold, before and after the catalyst. When they start going bad they usually cause a richer running engine, hence the soot. If only one side has a bad sensor, then only one set of exhaust tips will show the carbon associated with a rich mixture.

gpjli2

Tough call since you have only driven it 300 miles. My 06 has left side pipe darker since new. Motor was checked by Porsche and found "no fault". I am now at 32K miles and it runs great. Left side not as noticeable at this point. Oil use about 3000/qt. I have never noticed smoking however and so cannot tell you with certainty that there is no worry. With the milage you are doing you will never get a real sense of oil consumption. Unless it starts to smoke more I'd assume it was normal for that motor. Good luck.

Luxter

It is very well explained in the Guide 5 on Hartech web site that I referenced above.
It has to do with coolant flow bottom to top of engine block and split between heads and cylinders and thrust sides of cylinder banks #1 and #2. Baz did great job explaining it in detail.
Close to 30 pages so take your time....

edit:
Oooopss.... The guide grew to 72 pages, my apologies. Obviously it IS a problem.

neanicu

Do you drive a lot in stop and go traffic? I see you've only done 300 miles,so maybe it's time to open her up a bit on the freeway. Do a couple hundred miles at speed(70-80mph) and then see how it looks. Give the engine some time to run at operating temperature and the DME to settle all monitors.
Run a bottle of Chevron Techron fuel system cleaner right before you change your oil.
I'm not saying your problem can't be related to something else,but it doesn't hurt to give it a try.

Farside

Rijowysock & pongobaz, I guess the thing to do is I get the dealer's input into this ( if under warrantee it costs nothing ). I have done this and if the poo hits the fan I can refer back to written correspondence where I noted the issue ( I also have only had my 4s for 2 months so will argue that car was sold with this issue as I noted it after 3 weeks and about 400 miles) - not sure that that will solve all but I feel it gives something if there is a catastrophic issue.

When I took the car in to have these issues checked, they did a check up and as mentioned found nothing. Regarding the oil use, they did an oil change ( which was weird as they did one as part of my 111 point check three weeks earlier) and topped it up and told me to come in after 1000km to so that they can check actual usage vs what the electronic gauge says.

As stated in other threads, I am sure no one here minds paying for the oil if it's confirmed the excessive usage is part of the game for their car and not indicative of some larger issue.

If it turns out to be nothing the effort and worry is small price to pay for the awesomeness of a dream come true, along with the eye squeezing acceleration.

Macster

With no CEL, no untoward engine behavior, this strongly suggests there's not a problem.

Furthermore, I note you have only driven the car a few hundred miles and probably spread out over short trips.

Next I do not recall you saying if the plugs have been changed.

Thus you have a couple of things going on that can account for the smoke and the sooty exhaust tip.

Consider these points/suggestions:

Drive the car more. Once up to temp give the engine some cane at least once in a while. No need to thrash it on a grocery run, and obey all traffic laws, but drive the car harder, work that engine more. Long drives (50+ miles) at highway speed can work wonders.

Be sure you are using a top tier gasoline. And given you drive the car so little chances are the gasoline is not the freshest around any more. By driving the car more you fill up the tank more often and the gasoline is fresher. Also, buy from a busy station to ensure you get the freshest gasoline.

Consider a plug change. The plugs if not due to be changed on miles might be due to be changed on time. Furthermore, given the type of driving you engage in the plugs might just be getting a bit fouled and need to be changed regardless of miles/time.

Be sure the engine oil level is ok. Not too low, but not too full either.

And you need to learn how to accurately, consistently, check the oil level.

If there is some 'scoring' problem beginning carefully tracking/documenting oil consumption is vital if you have to make a case about this to the dealer.

Also, be sure the oil is fresh and of the right type. The wrong oil, or oil with a lot of miles on it can make its way through the engine. Now the path through the engine might not be past the rings, past the valve stems/guides/seal but through the AOS. Oil that is past its change by date can increase the amount of oil vapor in the crankcase and if the AOS ain't the best around this allows more oil vapor to be routed to the engine. I'm not up on the AOS vapor routing, exhaust routing of the 997 engine in your car but with previous engines one cylinder bank was "favored" with the output of the AOS more than the other.

If this is also the case with the 997 engine the differences in exhaust tips could due to the bank that is generating the heavier soot output being the bank that is having to burn a heavier load of oil vapor.

I have to point out that the exhaust gases pass through 2 converters, which convert (essentially oxidize/burn) the more harmful contents of exhaust gases into less harmful gases. Thus the appearance of the exhaust tips absent any signs of distress from the engine say more about the converters than they do about the engine.

Also, the converters (and the O2 sensors, the intake valves and so on) can also be affected by the type of driving you have been doing. The engine's combustion might not be all that great. Not bad enough (yet) to trigger misfires but bad enough to account for what you report seeing.

Unless the plugs are new/recently changed, change them.

At the same time, unless you are sure it is not necessary, have the oil/filter service done. Be sure you have the oil level noted on the work order -- and have the tech/service manager show you how to check the oil and be sure you get/see the same reading! -- so you can begin collecting oil consumption data in case things are happening internally in the engine that results in an increase in oil consumption.

At this time, while the plugs are being changed, you can push for at least having the suspected "bad" bank cylinders bore-scoped to at least confirm this is not a problem or worse case is that the signs of scoring are present.

Now the dealer might if nothing found want to charge you for this. No symptoms, and sooty exhaust isn't sufficient in this regard, no problem so the service department can't bill this time to the factory under any warranty. But the peace of mind I think would be worth an hour's extra labor.

Sincerely,

Macster.

rccman100

another dumb question, why do these cars seem to burn more oil relative to other cars? is that just the nature of high performance engines like this?

rccman100

@ Luxtor: Sorry. I was too lazy at the time . But I read through it now. got it!! thanks

I live in Switzerland..so cars here are usually meticulously maintained bcs they are uber expensive. this car sold brand new for $235k. the options alone were $29k (more than I've spent on all the cars in my life cumulatively..just for the options . I bought it from the same local dealer who sold it new to the one owner. all maintenance performed like clock work. So I'm probably worried about nothing. but will go have it checked out anyway. There is a periodic metallic buzzing sound that sounds like either a heat shield or something in the powertrain that I want them to check out anyway. I doubt it's related...

USMC_DS1

My car does not seem to burn any measurable amount of oil but I change the oil every 2-3K miles and/or 3-4 months.

Luxter

Hi RCCMAN,
I understand, it is quite long. It is one of the most informative (and technical and I am an engineer) writeups that I read to date.
Basel, my good friend's wife and two great kids live in Basel. Never been there, one day....
In fact we spent last weekend together with his daughter visiting Calgary for the summer. Both kids finished high school here and moved to Basel to continue their education.
Well, you have access then to some of the best Euro oils, probably more expensive than prices on NA continent, but at least you have lots of really good oil choices. Harftech mentions Castrol Magnatec 10W-40 (and some nano technology Millers oills) which is/are a pipe dream over here.

Macster's advice above is very sound. I would follow that to the dot.

One thing I would add is to make sure that your cooling system is restored to brand new condition (if not improved in fact) with fresh coolant, water pump and possibly low temp thermostat and 3-rd radiator. But all that is well covered by Hartech, so no need to repeat again.
Interestingly some cars exhibit oil consumption and some don't. I belong to the latter group, but I was getting some oil consumption before all my maintenance work and on Mobil 1, 0W-40 oil.
Your distance may vary of course.
All the best and keep us posted.
Don't hesitate to ask more questions, glad to help with my experience.
Cheers,
=L=

gpjli2

With all due respect to harteg and my fellow posters don't overreact to the scored cylinder wall thing. If your observation was always due to a fatal flaw in these motors there would be mass failures by now. As I stated my engine did this FROM NEW. The engine was scoped at that time and was sound. There was no wear or wall issue. Compression and bleeddown were A+. The fact that the motor runs better after 32k miles and the difference btwn tips is less as I accrew milage suggests that this condition can reflect a difference in tolerances between cylinder banks and does not portend disaster. A few motors will fail for one reason or another but imho you need to drive this one more and worry less, not visa versa.

user 72902

Good suggestion, however, make sure you drive your car long enough to get the oil hot for a sufficient length of time to burn off any water vapor or condensation otherwise your readings will be inaccurate. Your measurement will include water making the reading higher than the actual level of oil.

CAA

While we're on the topic, can anyone recommend a product to clean the exhaust tips?

rccman100

LOL. I was wondering the same

USMC_DS1

For my polished SS tips I use brake cleaner to remove any finger print oils. It cleans/removes oils and then evaporates w/o leaving an type of film behind. BTW, if you don't clean any finger/body oils off polished SS before the exhaust heats up you'll end up with finger print marks on them.