Engine data
911 Carrera, 911 Carrera 4,
911 Targa 4
911 Carrera S, 911 Carrera 4S,
911 Targa 4S
911 Carrera S, 911 Carrera 4S,
911 Targa 4S
(increased performance version)
Type M 96/05
Horizontally opposed engine,
liquid cooled
M 97/01
Horizontally opposed engine,
liquid cooled
M 97/01S
Horizontally opposed engine,
liquid cooled
Number of cylinders 6 6 6
Bore 3.78 in./96 mm 3.90 in./99 mm 3.90 in./99 mm
Stroke 3.26 in./82.8 mm 3.26 in./82.8 mm 3.26 in./82.8 mm
Cubic capacity 219.4 cu.in./3596 cm³ 233.3 cu.in./3824 cm³ 233.3 cu.in./3824 cm³
Net-horsepower, SAE J 1349 325 hp/239 kW 355 hp/261 kW 381 hp/280 kW
at crankshaft speed 6800 rpm 6600 rpm 7200 rpm
Net torque, SAE J 1349 273 ft.lb./370 Nm 295 ft.lb./400 Nm 307 ft.lb./415 Nm
at crankshaft speed 4250 rpm 4600 rpm 5500 rpm
Engine oil consumption up to 1.5 liters/1000 km
(1.6 quarts/622 miles)
up to 1.5 liters/1000 km
(1.6 quarts/622 miles)
up to 1.5 liters/1000 km
(1.6 quarts/622 miles)
Engine control Stationary high-voltage distribution, sequential injection, cylinder-selective knock-control, stereo oxygen sensor closedloop
control, diagnostic system, 4 overhead camshafts, Porsche VarioCam Plus, hydraulic valve clearance compensation



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This is from the 2006 owner's manual. You are within Porsche normal spec but it's hard to believe it until you see it in writing

 

How was the new motor broken in by the rebuilder? Did they run it through a break-in protocol with a break-in non-synthetic oil and then have you drive it with a non-synthetic for the secondary break in also. Sounds to me like maybe the rings aren't seated or broken in properly and using synthetic oil can prevent a proper wear-in or break-in process.

 

Oil usage on 997's seems to be all over the map. My -06 C4S burned virtually no oil at all. The -09 C4S needed a quart about every 1,200 miles and my current GTS maybe a quart every 4,000 miles or so. Pete's observation on the break in sequence is interesting though. I had no idea that kind of process is necessary but you have to think the rebuilder knows and gave directions accordingly.

 

I can't believe I've never seen the oil consumption figures in my owner's manual. Also cannot believe how much consumption is within spec. Crazy! My car burns a small fraction of that.

 

I couldn't tell you, it was rebuilt 3 years ago and only covered 10,000 miles in that time. I had not heard that before. Interesting! It has just had all three air oil seperators replaced with no joy. I filled it with oil, 287 miles and three days later it was low on oil once more. Completely baffled. Having borecope check tomorrow...
For some reason I think the crank defiantly has too much pressure. I can hear a faint wine at high rpm and I'm 99% sure if I checked the intake I would find a small pool of oil like before the AOS replacments.

One thing I am sure of is the crank position sensor is failing but that doesn't explain high oil consumption in any way.

 

That's a lot of oil consumption. with the miles driven, the break in time should be done a while ago.

as an example, I bought my 997 december 2017 and drove ~10k miles.
I have done two oil changes and she didn't require a drop of oil refill.

Does your car smoke blue when you start the motor? Check also the rear view mirror when you WOT in higher revs.

 

I had a mate follow me on a bike other day, under acceleration there is black smoke. On start up it seems OK. All soon clears after a minute or two of running. Seems too white to be oil to me!

I was at the garage today, took spark plugs out. Cylinder 5 and 6 had very fouled plugs. Dry carbon build up. The pistons also looked to have carbon build up particularly on those two cylinders. To be honest I think it's buggered from that alone. Getting a better camera tomorrow to see the bore. The camera wasn't clear enough for the bore. I can't see why the plugs would be fouled without bore scoring though?...

Same time, how can it be scored after 10,000 miles.. Not good!

 

That carbon could be an indicator for faulty piston rings.
Maybe not proper installed when the motor was rebuild.

I hope you get this sorted.

 

I'm a little confused - you say under acceleration black smoke has been observed. To me, that would correspond to the fouled plugs in cylinders 5 and 6, especially if the smoke is coming out the left side tailpipe (assuming you're running the OEM crossover catalytic converters). If you're running an X-Pipe or different exhaust, that could change on which side(s) the smoke would be seen. The engine builder may not have staggered the 3 ring gaps in the 3 piston rings in each cylinder, which is giving oil a direct pathway through the rings and could cause the fouled plugs and black smoke under acceleration.

On start up, you say there is smoke too, but it seems too white. So you have black smoke underway with fouled plugs and white smoke on startup?

If so, next time you start the car and see the white smoke, jump out and smell it. If it smells like burned coolant, that's a cracked cylinder wall or blown head gasket and you are getting coolant into the cylinder(s) when the cooling system is pressurized, and that's being burned on startup, which causes the white smoke. Depending how much coolant is getting into the cylinders it could have caused other issues - bent connecting rod, scored bore, etc.

You mentioned that plugs 5 & 6 were black and sooty - were any of the other 4 especially clean, like super clean - the coolant when it burns and becomes steam (and causes the white smoke cloud) will steam clean the tips of the plugs in those cylinders. You can test for a cooling system issue a couple of ways - one would be to get a pressurized cooling system tester and pump up the cooling system to 14 or 15 psi. It should hold pretty steady at that pressure. If the needle slowly falls down, you have a leak somewhere. If you do this test a couple times, then start the car, if the white smoke cloud is even bigger than before, you know coolant was being forced into the combustion chambers by the increased cooling system pressure from the test. Another way is to purchase a combustion test kit that will detect the presence of combustion byproducts in your coolant - you just pump a little coolant up into the tester and see how it reacts with the solution in the tester.