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Sooty exhaust pipes

Ill just go over the facts ..

Sooty tail pipes on one side .

5 Ltrs of oil PER year .. excessive .. 1 ltr is closer to the norm .

No knocking noises .

No misfires and im guessing no fouled spark plugs .

For me its mid range bore score im afraid ..


Now .. ive seen cars with this go for several years .. a Boxster ive seen for 2 years with the same as you but is still not fixed and still going .

Ive also read on here 4k from fine to its had it .

There is no set rule im afraid.

Ive seen excessive bore sore and they smoke like an AOS failure .. its bad .. very bad .

Other faults .. yes but in this case i think not .. over fueling .. leaking injector , low compression .. basically anything that causes an incomplete combustion cycle ..

But with this there will be fault codes .. the car aint stupid .

Oil burning doesnt tend to give fault codes .. we are not talking pints of oil rather a spray or a dribble now and then and the car will adapt to this so fuel trim figures are something you could look at.

Too be honest you need a bore scope check done as that will confirm it one way or the other .

Imho the car wont go bang .. but it wont get any better ..

Its we buy any car or a rebuild im afraid and whilst i agree Hartech are the industry leaders any Porsche specialist can do the work .

resale value and Hartech is a Forum question and not one i concern myself with ... a little blunt but we all rebuild engines .

Edit ..

just to point out Bore score is groves worn into the cylider lining .. a channel that allows oil to bypass the piston rings and end up getting burnt along with the normal running ... drag your finger nails over a bar of soap .. same thing .
 
Thanks for all the advice folks and taking the time to post.

I love the car and will keep it forever, so will definately book the bore scope.

Silly question - How are the cylinders numbered? I read about No.6 wearing first, but I dont know which one that is?

Also - if there is some scoring, but i am not experiencing any reduction in performance, just the pain of keep topping up the oil, will the problem definately get worse and possibly cause more damage?

Thanks
 
Face the car from the rear .. you are looking at the crank pully or drive belt end ..

The cyl numbers are 1,2 3 left side and 4,5,6 right side ..

No1 is the closest to you left side .. number 4 is the closest to you right side .

All Porsche cars are numbered this way .


Oil can bypass the piston rings causeing smoke due to scoreing .

The damage is already done but will get worse .. the really bad stage is when it starts knocking as thats a worn piston slapping the bore .

Basically though if its scored the damage is already done , you need a liner and a piston .. it will get worse but your pretty much the same .. you will still need those items .

Ive never seen one go past the loud knocking stage so cant comment if you keep driving it after that though .
 

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Just to point out the exhaust outlet for the right bank is on the left and obviously vice versa.
 
Thanks again for the helpful replies.

Another quick question - Is the Oil presure gauge any kind of indication of engine performance? Only I read in the manual that it should sit around 3.5 Bar at 5000 RPM, but i use mine every day and rarely see it come away from the max - 5 Bar. Which sort of gave me some confidence that I wasnt losing any compression pressure through any bore scores. Or is the gauge too crude to pick this up?
 
The two are unrelated. You can make great oil pressure and have ruined bores, there shouldn't be any oil there, it won't affect pressure readings.

MC
 
These guys - Archer Motorsport - are local to you, just came highly regarded in this review;
http://911uk.com/viewtopic.php?p=1438500#1438500

Might be worth a visit for an opinion at least?

Either way, make sure whoever does the borescope knows what they are talking about... there is a difference between normal bore marking and actual scoring.
 
I have not had a chance to get the bores checked yet, and been careful about warming up and oil levels.

But today the 'check engine' light came on just after I set off this morning.
I have read that there are many reasons for this warning light, and it often sorts itself out. But I wondered if there was a chance it was due to a problem related to my black exhaust/burning oil concerns?

Looking around the web I did find an 'iCarsoft Multi System Diagnostic Tool' recommended by Porsche owners for getting feedback on warning lights and resetting them. Wondered what people thought?

Thanks
 
Just seen your location.. RPM are 10 minutes away from you and can do the borescore, about £100/£150 if I remember rightly.
 
Its a basic tester that will do the job .. you need the fault codes in the dme .. then post them .

For a score issue then fouled plugs causeing a misfire but there are several other things that can cause an eml or indeed a misfire with cracked coils being the most common .

Basically we need a fault code to go further im afraid .

Turn the ignition on but dont start the car .. is the oil pressure reading at 0 or higher ? .. it should read zero .. if not you have a faulty oil pressure sender.

Bore score has no efect on oil pressure .

Is the car running ok or does it sound lumpy ?

It might be lambda sensor ageing which is basically .. they are getting old .
 

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