For sure - this issue didn't exist in older Porsches; 928s and air cooled 911s go hundreds of thousands of miles with perfect cylinder walls. You say better tolerances, but what you should say is tighter tolerances, which is where the problem stems from. In having to chase higher efficiency = greater compression and power from less displacement to meet more stringent emissions and mileage regulations, that tighter tolerance is a major contributor the the problem - not so much in the 997.1 where it's a piston rocking issue due to the offset on bank 2 with the skirt touching the cylinder wall, but on the 997.2 where it's a cold seizure at the bottom of the stroke when the piston is actually larger than the bore due to irregular thermal expansion and ovality issues, you bet.

To say the bore scoring issues are not fully understood isn't accurate. They've very well understood as well as the nuances of what causes them and the differences between the engine generations. You may just not be fully educated on it, which is fine, but it is very well understood by Hartech, FSI, LN, Jarno, and the other major engine players out there.

 

Yeah, good one. Go ahead and search, you'll find just as many experts telling you that the issue is *definitely* leaking injectors causing oil washout on the walls.

Either way, oil analysis isn't going to help catch that. Bore scoring is not a slow thing: you get a rapid increase in metals, and once it happens there's nothing you can do. So all that annual UOA is going to do is tell you that you're screwed. You're better off just using good gas and injector cleaner, being religious about letting the engine warm up fully before you flog it, and if you're really paranoid checking the fuel trim now and again.

If you think some brand of oil offers better protection against bore scoring go ahead and use it. But I see no value in doing regular UOAs. It's just Internet forum paranoia.

 

Leaking injectors is also a contributor, especially in the DFI motors where they leak directly into the cylinders.

I get that you don't care, that's fine. In school I was a 100 on a test kind of guy (like lowest metal from best oil). If you were happy with a 96 being good enough like with Mobil 1, cool.

 

Over half of the failures we see are broken rods from spun rod bearings. They are by far the most catastrophic, often taking out the crank, crank carrier, a rod, and the case. Here are a few pics from one we disassembled today that did all of the above and also trashed one of the heads pretty good. These are preventable, oil related failures and a UOA is one of the best tools available to monitor if your oil selection, fill level, and change interval are providing adequate protection. There have also been several occasions where the wear levels started spiking and the owner elected to do a proactive rebuild and saved $3-5k in core charges. Endurance racing does not void our warranty on our engines, but failure to follow our oil selection, fill level, and change interval guidelines, and failure to monitor wear levels through UOA’s will.

As for the OP’s question, it wouldn’t hurt to drain a little oil from the sump and get an analysis done at 500-1000mi. I would recommend having a lager container underneath, in case things get out of hand. A clean 5 gallon bucket and a 50 micron bucket filter can come in handy as well.

 

This thread contains a telling spread of posts. The latest is by an engine rebuilder - someone who has to be right almost every time, or they are out of business. Petza's post represents the next level down (but not by much), where he has a tremendous amount of firsthand knowledge and is very well studied (he got all those 100's, right? ). I am somewhere below that, maybe well below that. I think the three of us (and many others like us) share a passion in learning and passing along reliable knowledge, and we try to do it in a cordial manner.

And then there are others, fortunately not too many, but enough to taint things. Those who are so adamant about being right that they cannot seem to even comprehend what others write. There is a recent thread about this. Welcoming New Owners or Prospective Owners - Rennlist - Porsche Discussion Forums This type of poster seems to easily devolve into making unpleasant and borderline insulting comments.

 

I can only lead the horses to the water...can't make them drink, but that's OK.

 

Look, I'm not talking about racing: that's a different situation. And even in the cases above the statement is not that UOAs would've prevented rebuilds, just potentially reduced the rebuild cost. It's diagnostic of the bearing damage, not preventative.

I mean, let's get serious here about that example: you guys seeing a lot of spun bearings on street cars that have been properly maintained? That's not something that happens regularly unless something catastrophic happens, which again UOA won't help you with. And let's say you do have a bad bearing on a street car: you're going to hear the noise long before you kaboom your engine like that so long as you pay any sort of attention to your car. The damage in the photo above happens on the track where you can't hear the noise and are at sustained high RPMs.

I'm not trying to insult anyone, I assure you, and I'm not going to get into a "who had better grades in college" competition My opinion is based on my engineering experience and many years of doing most of the work on my own cars: I just can't see the point of doing regular UOAs on a street car. Even after all the posts here it doesn't seem that there's any useful, *actionable* data that's going to make any sort of difference that matters: it all seems to be based on paranoia, wishful thinking, and playing in the noise of the data.

Go for it if it makes you feel better, but I can't see any evidence that supports regular UOAs helping you prevent bore scoring, bearing issues, or whatever. As a diagnostic tool it can tell you that you're hosed because of one of those problems, but as a regular preventative thing? I think people are kidding themselves.

 

Moose - you seem to not get it. Your points are made, but you are failing to realize that we do these(UOAs) because these cars are for the most part hobbies to us and we like to tinker.
I get regular UOAs and I wait like a little kid at Christmas for the reports to see the results, trends, effects of the changed oil brands and other things. My wear metals have been consistently high over the last 50k miles, but the car runs perfect, burns no oil - now I switched to another oil and I can't wait to see the results. Get it?

 

Hobbies? Yes.

Since my first post on this thread I've changed oil brands once and am about to do it again. So I haven't done a UOA for a while. Driving to 130K miles on Mobil One with admirable results I then started adding MoS2 and the results stayed the same. So at 145K miles I switched to LiquiMoly 5-40 with a can of MoS2 (yeah, I know, a can and a half is what's right). I figured with my mileage a bit of extra viscosity couldn't hurt. And a friend pushed me in that direction. And then there's this Forum. I was about to send for results when I got a bug to add Injector Defender, but to get the free shipping I added $130 of DI40. With that commitment (thanks, all of you!!!!!) there isn't a lot of point in a UOA until I run a couple cycles of that oil. So ... I've got nothing. I miss my data.

Note ... With the addition of Injector Defender the PDK seems to be shifting a bit harder. Is it just me looking for something? Don't know. I've got a spirited drive scheduled in tomorrow's rain so I'll run through this tank of gas and I should "know" more soon.

Yeah, a hobby 😀

Still looking forward to my next UOA.

 

That perfectly describes me as well, you know. I just don't like wasting effort or money on things that don't move the needle.

And if that's actually the thing then just tell people like OP that when they ask. "Hey, they're interesting data, but not critical." Because despite what you're saying, half the posts in this thread are about how your Porsche is going to explode from bore scoring or bearing wear or whatever if you don't do UOAs, and how using Mobil 1 is the automotive equivalent of beating your spouse, lol. It's internet scaremongering, and a lot of it is from people who don't understand what UOAs can and can't do. It's a useful tool, but only sometimes.

I swear, next halloween I'm dressing as a scratched Nikasil liner and showing up at all your doors...

 

Maybe a typo but what is DT1? DI40? Running injector defender should not have anything to do with PDK shifting harder. Possibly colder weather?

 

Yep, typo or autocorrect ... DI40. Thanks for spotting that. I'll edit it after I post this.

I agree, PDK shifting shouldn't be affected. With going on 10 years of all season driving over the course of 120K miles I know how things are with the car. And after about 25 miles of Injector Defender the PDK shifting altered. Maybe motor response changes as the motor runs better? Maybe in my head as I'm looking for justification for the cleaner. Or maybe paranoia that disturbing old dirt can have adverse affects.

Anyway, I'll have a few hundred extra miles to see what happens tomorrow.

 

Awesome, NP. Thanks

 

"I swear, next Halloween I'm dressing as a scratched Nikasil liner and showing up at all your doors..." That's hilarious. Also, would be very frightening as now even the Nikis
are scoring - imagine the horror to all those that just rebuilt using them!

 

Nikasil is effectively impervious to scoring. There are very few things that can take out Nikasil:
1. High sulfur fuels. Not a concern for almost all of us....
2. Running the engine without oil.
3. A very badly leaking injector. This is what oil analysis is for. High fuel dilution is the kiss of death in any engine, period. High wear and serious issues are usually accompanied by elevated levels of fuel dilution.

In the end, it is pennywise and pound foolish not to spend $50 periodically to check the health of your engine. I do it even in my cars that cost less. Still a lot cheaper than pulling the engine.