Exhaust port carbon deposits. What is normal?
11-13-2018, 08:14 PM
#16
Rennlist Member
My 2011 4s are sooty too. I use no oil over 5,000 km between oil changes, my oil filter has no particles in it, the car runs great......I am worried that there is nothing wrong with my 911........ I'm worried that I dont drive it like a race car often enough......eventually I will just stop worrying and just smile every time I start it. Oh and btw , every 5,000km it decides to throw a pdk code in the spring for no apparent reason other than maybe the battery tender was left off too long and the battery voltage was a little shaky
11-14-2018, 12:38 PM
#17
There have been naysayers regarding the 9A1 motor and whether the intake valves get washed or not. The lack of a problem is anecdotal evidence that the Porsche engineers did a good (or even great) job, one way or the other. I believe Porsche had (and has) their DFI act together.
On the other hand, the exhaust valves don't get washed. To the OP ... change the oil to get a reference point (unless, or even if, you have full maintenance history ... you may want to do all the services). Clean your tail pipes. Then get out and drive. After enough miles check the oil, check the tailpipes, and be cautious to avoid Forum Flu (the emotional fear that the sky is falling on your ride).
Welcome, you've got a great car, congratulations, enjoy.
On the other hand, the exhaust valves don't get washed. To the OP ... change the oil to get a reference point (unless, or even if, you have full maintenance history ... you may want to do all the services). Clean your tail pipes. Then get out and drive. After enough miles check the oil, check the tailpipes, and be cautious to avoid Forum Flu (the emotional fear that the sky is falling on your ride).
Welcome, you've got a great car, congratulations, enjoy.
11-14-2018, 12:46 PM
#18
RL Community Team
Rennlist Member
Rennlist Member
Many thanks for all the responses to my questions. All were great insights and helpful information. I have no information as to the maintenance history of my Porsche except that the seller supposedly gave it an oil change before shipping it to me. I will go out today and drain off some oil and will know if it is new oil or not. This car with 54K miles on it is undistinguishable from a new car per interior and exterior body and paint. Hopefully that degree of care was also lavished on the engine. I am wondering if the thin motor oil (5W40) would contribute to cylinder wall scoring. I am used to using 20W50 synthetic in my 60 Alfa.
In SC, I use 5W-40 weight year round since on the handful of 15-20 degree F days we have in the winter, I can just drive something else. If I lived in the NE, MN, IL, etc, and drove my 997 over the winter, I'd put in 0W/40 around Oct/Nov and then change it again to 5W/40 in the April.
11-15-2018, 11:46 PM
#19
Racer
There have been naysayers regarding the 9A1 motor and whether the intake valves get washed or not. The lack of a problem is anecdotal evidence that the Porsche engineers did a good (or even great) job, one way or the other. I believe Porsche had (and has) their DFI act together.
On the other hand, the exhaust valves don't get washed. To the OP ... change the oil to get a reference point (unless, or even if, you have full maintenance history ... you may want to do all the services). Clean your tail pipes. Then get out and drive. After enough miles check the oil, check the tailpipes, and be cautious to avoid Forum Flu (the emotional fear that the sky is falling on your ride).
Welcome, you've got a great car, congratulations, enjoy.
On the other hand, the exhaust valves don't get washed. To the OP ... change the oil to get a reference point (unless, or even if, you have full maintenance history ... you may want to do all the services). Clean your tail pipes. Then get out and drive. After enough miles check the oil, check the tailpipes, and be cautious to avoid Forum Flu (the emotional fear that the sky is falling on your ride).
Welcome, you've got a great car, congratulations, enjoy.
11-16-2018, 02:45 AM
#20
Tail pipes get dirty. Unless you are experiencing excessive oil consumption, I would not worry.
Temper what you read here. Scored cylinders? Sure it can happen if the car is abused, but properly warm your car and don't worry about it. Forums made me paranoid about worn valve guides in my air cooled cars, but I never actually had an issue.
Temper what you read here. Scored cylinders? Sure it can happen if the car is abused, but properly warm your car and don't worry about it. Forums made me paranoid about worn valve guides in my air cooled cars, but I never actually had an issue.
I recently purchased a 2009 Carrera 2 S with 54K miles on the odometer. I noticed that the exhaust tips have carbon deposits that wipe off when rubbed with a finger. In my experience, this much carbon at the exhaust outlet means that the engine is running rich. I would think that the Porsche's engine management would provide a perfect air fuel ratio so now I am wondering if the engine has scored cylinder walls and worn piston skirts that would allow oil into the combustion chambers. I removed the cats and all six exhaust ports had equal carbon deposits about one millimeter thick that was powdery and could be easily scraped off. I have not detected any clicking sounds at idle so far. My question is whether or not carbon deposits as I have described are normal or not. Do I have cause to get the cylinders bore scoped? Many thanks in advance.
11-20-2018, 04:49 PM
#21
Thanks to all of you for your great inputs to my question. As a follow up, I had to remove eighteen ounces of motor oil (over fill) to get the computer oil measure on the top line with the white showing. Now I can drive the car and determine oil consumption and maybe determine if the over fill was causing the heavy carbon deposits. My next task is to replace the spark plugs and see what the old ones look like.
11-20-2018, 05:06 PM
#22
18oz, 1.25qts?! That's quite an overfill. No wonder things were a little dirty!
Thanks to all of you for your great inputs to my question. As a follow up, I had to remove eighteen ounces of motor oil (over fill) to get the computer oil measure on the top line with the white showing. Now I can drive the car and determine oil consumption and maybe determine if the over fill was causing the heavy carbon deposits. My next task is to replace the spark plugs and see what the old ones look like.