Porsche 911 (997.1) - potential bore scoring UOA?

[Slowslowcar]

Only 1.6k miles on the oil (not 3.5k miles). Consuming about 1qt per 1.2k miles. Worried about potential bore scoring. Thoughts?

 

[Trav]

Use a boroscope down the spark plug hole, if its scored you will see it.

 

[RooflessVW]

Nothing in your UOA indicates bore scoring. The difference between 4 and 9ppm is statistical noise.

I'd look to your AOS as the cause of consumption.

 

[RooflessVW]

Use a boroscope down the spark plug hole, if its scored you will see it.

The early stages of scoring in the M96/97 cannot be detected through the spark plug hole.

It starts at the bottom.

 

[Slowslowcar]

Nothing in your UOA indicates bore scoring. The difference between 4 and 9ppm is statistical noise.

I'd look to your AOS as the cause of consumption.

thank you, at what point do you get concerned/need to look into? if the trend is heading up
?

 

[RooflessVW]

thank you, at what point do you get concerned/need to look into? if the trend is heading up
?

Well, there's nothing you can do to stop it or even slow it.

If you have an engine that has started to develop bore scoring then it will continue and the answer is a full rebuild.

If it worries you the only way to know for sure is to drop the sump plate and inspect the bottom of the cylinders with the pistons at tdc. I think you can see 4 of the 6 this way.

 

[Trav]

The early stages of scoring in the M96/97 cannot be detected through the spark plug hole.

It starts at the bottom.

I guess it doesnt take long before it moves up the bore though if it is real scoring from damaged components,

 

[Wrenchturner44]

I quart of 1,200 miles is not much depending on the kind of driving you are doing. I would also make sure that your oil consumption is not being caused by leaky valve seals, which is common part to be replaced on that engine. This can be done with the engine in the car, but it takes some special skill and tools to get it done properly. Take a L@@K at this link to learn more. http://forums.pelicanparts.com/porsche-911-technical-forum/490990-replacing-valve-stem-seal.html

Given the age of the vehicle, and the oil consumption you are describing, my advice is to start with replacing the valve seals before you start worrying about the cylinder bores.