Even the mighty Porsche DI succumbs to deposits

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Big problem here is likely overly-frequent oil changes with an oil that has a fairly high degree of volatility, and probably not something like Mobil-1, or the full synthetic ExxonMobil XD-3 oils. The owner might think that they're 'protecting their investment' by doing frequent changes on their expensive new ride, but in fact, those frequent changes are causing the oil to spend most of its time in the initial 'boil off' phase, which causes much of the contamination that you see. "Overmaintenance" (ie: changing oil too frequently) is one of the worst possible things one can do for their vehicle (and it seems to be quite an epidemic on this website, unfortunately!).
 
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 Originally Posted By: pitzel
Big problem here is likely overly-frequent oil changes with an oil that has a fairly high degree of volatility, and probably not something like Mobil-1, or the full synthetic ExxonMobil XD-3 oils. The owner might think that they're 'protecting their investment' by doing frequent changes on their expensive new ride, but in fact, those frequent changes are causing the oil to spend most of its time in the initial 'boil off' phase, which causes much of the contamination that you see. "Overmaintenance" (ie: changing oil too frequently) is one of the worst possible things one can do for their vehicle (and it seems to be quite an epidemic on this website, unfortunately!).
I have never heard of this boil off phenomenon. Are you saying that every car experiences this after an oil change, or it mostly regards high performance vehicles?
 
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 Originally Posted By: Art_Vandelay
I have never heard of this boil off phenomenon. Are you saying that every car experiences this after an oil change, or it mostly regards high performance vehicles?
Every car/engine experiences this after an oil change. The NOACK volatility test quantifies the extent that this occurs with a particular oil under standardized conditions. Losses are the greatest in the first 1000-2000 miles, and taper off after that. "high performance" vehicles are particularly susceptible because their owners usually have the disposible income to take them for oil changes, and the belief that oil changes are required more frequently on a more expensive vehicle. Also, in addition to excess deposits caused by overly frequent oil changes, there is degradation of other gas path components and instruments caused by the same. I'm willing to wager that the vehicles that suffer from these deposits also have poor oxygen sensor and catalyst life compared to their appropriately maintained peers. Of course, direct injection naturally makes the deposits on the intake valves much greater, and facilitates accumulation since there isn't a natural 'washing' of petrol vapours over the intake valve every time it ingests fuel from the intake (since fuel is directly injected), so there's literally nowhere for the oil-derived PCV deposits to go other than to create such a 'gunk' on the valves and/or in the intake tract more generally. An interesting maintenance problem indeed.
 
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 Originally Posted By: ADFD1
I would love to see if adding MMO or TCW3 to the gas would help slow that process down. If it were my ride I'd certainly give it a try.
No fuel gets to the valves, therefore no help from there, as 'Mr. Vandelay' said. Not to sound like a broken record, and this is the last time I will post it here, but: Best actual solution to me is to get rid of the PCV gunk coming into the intake completely. This is exactly what VW says would be a solution in their patent for the engine. For example via a pcv bypass such as this: http://www.bobistheoilguy.com/forums/ubb...475#Post1463475
 
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 Originally Posted By: saaber1
No fuel gets to the valves, therefore no help from there, as 'Mr. Vandelay' said. Not to sound like a broken record, and this is the last time I will post it here, but: Best actual solution to me is to get rid of the PCV gunk coming into the intake completely. This is exactly what VW says would be a solution in their patent for the engine.
That sounds logical.
 
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Yes, I have heard of the phenomena. But more as it relates to highly volatile carrier oils for ZDDP and the resultant catalytic converter poisoning. Thus, the advent of SL and SM oils to lower the dosage of phosphorus ingested by the cats after initial fill of fresh oil.
 
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 Originally Posted By: saaber1
Definitely the solution is we need to start doing 30k oil changes
Guided by UOA (not interpreted overly conservatively, ie: most Blackstone analysis' we see posted in the UOA section), and the use of appropriate oils, absolutely.
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Yes, I have heard of the phenomena. But more as it relates to highly volatile carrier oils for ZDDP and the resultant catalytic converter poisoning. Thus, the advent of SL and SM oils to lower the dosage of phosphorus ingested by the cats after initial fill of fresh oil.
The modern oils are much better than in the past, but it takes so very little oil in the intake to cause the horrific results we see in the pictures... The manufacturers have had to tighten up the volatility specs just to reduce problems like what we see in those pictures, and they're only going to continue to tighten as time goes on, to the point where only full synthetic products will be suitable. Direct injection just makes using a lower volatility oil, and changing it less frequently even more imperative.
 
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 Originally Posted By: saaber1
 Originally Posted By: ADFD1
I would love to see if adding MMO or TCW3 to the gas would help slow that process down. If it were my ride I'd certainly give it a try.
No fuel gets to the valves, therefore no help from there, as 'Mr. Vandelay' said. Not to sound like a broken record, and this is the last time I will post it here, but: Best actual solution to me is to get rid of the PCV gunk coming into the intake completely. This is exactly what VW says would be a solution in their patent for the engine. For example via a pcv bypass such as this: http://www.bobistheoilguy.com/forums/ubb...475#Post1463475
Agreed, but isn't there a residual effect of the top oil mixed in with the gas? I'm not suggesting it will stop the problem, just wondering if it will slow it down any. Those pitures are a mess. AD
 
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 Originally Posted By: pitzel
Guided by UOA (not interpreted overly conservatively, ie: most Blackstone analysis' we see posted in the UOA section)
Which apparently you have not bothered to look at. The 40+ UOAs for the 2.0 FSI show that all oils are shot by around 5k miles in that DI engine. I'm giving up on this topic. It's not worth the time. Can you guys please offer your comments on this "30k oil changes is the solution"?
 
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DI engines are destroying most motor oils. This is why Scott and Terry went to seek Renewable Lubricants Inc.
 
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 Originally Posted By: ADFD1
Agreed, but isn't there a residual effect of the top oil mixed in with the gas? I'm not suggesting it will stop the problem, just wondering if it will slow it down any. Those pitures are a mess.
Interesting AD. This makes me think of the claim asserted by redline for their SL1 fuel injector cleaner. They say something like it survives the "blowby/recombustion" process (my words not theirs). I don't buy redline's assertion personally, but it is an interesting Q as to what affect fuel additives (if any) could have via the volatalized "gunk" coming through the pcv.
 
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Seems as if DI engines aren't all they are hyped up to be. I wonder if regular top end cleaning with Seafoam through the PCV system would work?
 
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Uh, guys, this is a direct injected engine. The fuel doesn't contact the back of the valves. That's what's causing the problem in the first place. How is the fuel or any additive going to make any difference? Ed
 
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 Originally Posted By: saaber1
Which apparently you have not bothered to look at. The 40+ UOAs for the 2.0 FSI show that all oils are shot by around 5k miles in that DI engine.
I'm assuming you're referring to the chart you posted earlier: http://i140.photobucket.com/albums/r34/saaber1/uoa10b2.jpg Either I'm blind, or I don't see even a single UOA that is showing that the oil is *anywhere* near condemnation limits in any of those engines, or even half-near. TBN's are all in the 5-6 range, (really don't want to get much under 2). Insolubles are low. Fuel contamination is pretty much non-existent. No viscosity issues. Per unit iron is tapering off as a natural break-in process takes place. There isn't a UOA there that tells me that at least a 12-15k interval is out of the question with any of the oils used. Swap the filter out at 12-15k, and replace a quart, run to 20k, and the do an oil change at 20k would be my initial recommendation based on that spreadsheet of data. GC's not really an extended drain oil (and is really over-hyped), but if a true extended drain product were used (ie: Esso XD-3 0W-40, Amsoil 0W-30/40, etc., with dual gas diesel ratings and TBN to match), 25k with just a filter swap isn't really a stretch at all. I know people freak out when I'm suggesting they should change their oil 10% as often as their grandpa did on his cars, on a car that costs 20X as much, but my recommendations are based on science, not junk advertising or folklore from the quickie-lube industry.
 
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Can blame that on owner neglect. Improper maintenance or doesn't drive the car often. Poor fate to a Porsche They should give me the keys to it, i'll take care of it. For a car that expensive, i'd change the oil 3k/3months. Not worth having problems. If you can afford a Porsche, you afford doing frequent maintenance.
 
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 Originally Posted By: edhackett
Uh, guys, this is a direct injected engine. The fuel doesn't contact the back of the valves. That's what's causing the problem in the first place. How is the fuel or any additive going to make any difference? Ed
Well that sums it up, my bad. Glad I don't own a DI engine. JMO AD
 
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 Originally Posted By: edhackett
Uh, guys, this is a direct injected engine. The fuel doesn't contact the back of the valves. That's what's causing the problem in the first place. How is the fuel or any additive going to make any difference? Ed
It only would if it "survived the combustion process" like redline is claiming. If it did do that it would likely be an agent in the crankcase gases going through the pcv system and back into the intake. I don't think it does survive, and if it did, it's effect would probably be minor I would think. But it is an interesting Q.
 
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