# 520d F11 added oil to diesel.. wow!



## Pierre Louis (Oct 23, 2011)

TDIwyse said:


> For that to be true the scientists and experts at Infineum would have to be wrong when they say "Confidence in the test was further verified by *excellent correlation with field trial data*."
> 
> And this research would have to be wrong:
> 
> ...


The test is good, as above. The data is lacking as in my "statements" which I guess according to your interpretation, must be "lying". No question about it. You are reading into the words "field test data" are different from actual field failures ascribed to lubricity. Its similar to the speed limit debate....

PL


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## Nadir Point (Dec 6, 2013)

TDIwyse said:


> But the occassional delivery of out of spec lubricity fuel (verified by the Infineum results ... some being WAY out of spec at raw ULSD levels) will no doubt hurt the longevity of your FIE. No doubt about that.
> 
> Also, there's huge amounts of evidence from the VW TDI NHTSA investigation, and multiple re-designs of the Bosch HPFP, that we saw a large and widespread FIE issue due to insufficient lubrication and the design of the initial versions of CP4 pumps...


You would need to have your head buried pretty deep in the sand not to see what's going on here. The only question is how many bad tanks of fuel and how long or how many miles for the part(s) to fail.


d geek said:


> Again I ask: How did ULSD ruin your injectors? Please explain so we can understand how you concluded this. Thanks.


It doesn't take a tribologist to put 2 and 2 together: 80,000 miles and injectors shot. Maybe I should be more specific and say the "crapshoot fuel system" in this country, rather than just "ULSD."

Would that be any easier to understand?


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## d geek (Nov 26, 2008)

Nadir Point said:


> ...
> It doesn't take a tribologist to put 2 and 2 together: 80,000 miles and injectors shot. Maybe I should be more specific and say the "crapshoot fuel system" in this country, rather than just "ULSD."
> 
> Would that be any easier to understand?


That your injectors were bad at 80k mi is not in doubt. But there are other things besides lubricity that could ruin them. And it would take some forensics to determine what that was. Whether an additive could have saved them is an open question. Additives cannot cure every bad batch of fuel (water, gasoline, sediment, etc)


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## Nadir Point (Dec 6, 2013)

d geek said:


> That your injectors were bad at 80k mi is not in doubt. But there are other things besides lubricity that could ruin them. And it would take some forensics to determine what that was. Whether an additive could have saved them is an open question. Additives cannot cure every bad batch of fuel (water, gasoline, sediment, etc)


So what you are saying is: you have no clue?


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## d geek (Nov 26, 2008)

Nadir Point said:


> So what you are saying is: you have no clue?


I can do nothing but make educated guesses, which evidently isn't any different than what you've done. :dunno: Without disassembling the injector and looking at the parts under magnification I'm not clear on how anyone could determine the root cause of the failure.

Like I said before- I'm all for improving fuel lubricity, but I won't make more of it than it already is. Low lubricity is most likely to impact the internals of the HPFP. Thankfully, BMW saw fit to spec improved coatings on the HPFP internals (possibly the injectors as well) in order to deal with the lower lubricity in US fuels. Compared to VW/Audi, BMW hasn't seen anywhere close to the same percentage of HPFP failures in their diesels. The only BMW diesel HPFP failure I've seen reported here on Bimmerfest was from Denmark. I asked that poster follow up questions and they never answered.

So bottom-line I am just really curious to know if your injectors failed due to low lubricity or some other issue. I think its much more likely they failed due to contamination of some sort, but this is only a guess and I'd rather hear the explanation. I'm not sure why that seems to bother you :dunno:


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## Pierre Louis (Oct 23, 2011)

d geek said:


> I can do nothing but make educated guesses, which evidently isn't any different than what you've done. :dunno: Without disassembling the injector and looking at the parts under magnification I'm not clear on how anyone could determine the root cause of the failure.
> 
> Like I said before- I'm all for improving fuel lubricity, but I won't make more of it than it already is. Low lubricity is most likely to impact the internals of the HPFP. Thankfully, BMW saw fit to spec improved coatings on the HPFP internals (possibly the injectors as well) in order to deal with the lower lubricity in US fuels. Compared to VW/Audi, BMW hasn't seen anywhere close to the same percentage of HPFP failures in their diesels. The only BMW diesel HPFP failure I've seen reported here on Bimmerfest was from Denmark. I asked that poster follow up questions and they never answered.
> 
> So bottom-line I am just really curious to know if your injectors failed due to low lubricity or some other issue. I think its much more likely they failed due to contamination of some sort, but this is only a guess and I'd rather hear the explanation. I'm not sure why that seems to bother you :dunno:


I for one went into 335d ownership with eyes wide open. You are talking about an engine that is at the cutting edge of diesel performance and technology. There are risks with this. The choice that would have eliminated such risk would have been a 4 cylinder Camry. For me, the car is a 911 replacement/daily driver/practicality-added beast.

BMW is not known to be conservative in their designs or execution, as Mercedes or even Porsche tend to be. The 3-series is the most consistent, bread and butter line, that BMW has. The price would be much higher if the tech wasn't mostly "ordinary" (as opposed to Mercedes "perfection" - at least in the E-class and above) so you still get what you pay for.

The way European cars are made does not always translate well to North American driving and maintenance expectations either. NA drivers abuse their cars in a different way than Europeans, especially with the "stoplight grand prix," long distance driving, and other such rituals. Europe is a bit colder climate-wise, and yes, has better fuel overall.

PL


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## Nadir Point (Dec 6, 2013)

d geek said:


> I think its much more likely they failed due to contamination of some sort, but this is only a guess and I'd rather hear the explanation. I'm not sure why that seems to bother you :dunno:


Then maybe you can explain your hypothesis, considering there were no other failures and the car ran fine right up until the time it started missing and throwing codes, with exception of declining fuel mileage, which BTW was a long term symptom, consistent with the chronic condition of low lubricity slowly eating up the injectors.

Have you actually ever even driven a diesel vehicle with "contaminated" fuel? They don't run well, if at all.


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## Pierre Louis (Oct 23, 2011)

Nadir Point said:


> Then maybe you can explain your hypothesis, considering there were no other failures and the car ran fine right up until the time it started missing and throwing codes, with exception of declining fuel mileage, which BTW was a long term symptom, consistent with the chronic condition of low lubricity slowly eating up the injectors.
> 
> Have you actually ever even driven a diesel vehicle with "contaminated" fuel? They don't run well, if at all.


Sometimes its best to use the most likely true words: "I don't know."

PL


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## d geek (Nov 26, 2008)

Nadir Point said:


> Then maybe you can explain your hypothesis, considering there were no other failures and the car ran fine right up until the time it started missing and throwing codes, with exception of declining fuel mileage, which BTW was a long term symptom, consistent with the chronic condition of low lubricity slowly eating up the injectors.
> 
> Have you actually ever even driven a diesel vehicle with "contaminated" fuel? They don't run well, if at all.


I don't have a hypothesis for your failure because I don't have enough info to form an educated guess. I was hoping you could explain why you concluded that the root cause was lubricity. I think we can see now you're guessing too.

I think a quality additive will help with potential water in your fuel as well as lubricity. Waste motor oil won't do this, btw.

In my 13+ years of driving diesels I never did encounter obviously contaminated fuel. I did use additives most of the time (Power Service DFS mostly). I'm certain that it helped with lubricity, but can't know if it ever dealt with significant amounts of water. I never found water in my fuel filter separator either.


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## TDIwyse (Sep 17, 2010)

Nadir, it could also be lack of adequate filtration on the fuel. Caterpillar did extensive studies on injector lifespan and fuel contamination and came to the conclusion that they would move to 2um filters for their high pressure applications. The BMW fuel filter is not spec'd to be that good ...

http://pdf.cat.com/cda/files/3022934/7/PEHP7046-03.pdf

_*Size of Contamination*
A particle five microns across can 
damage fuel systems._


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## josh1e (Jan 7, 2012)

Just thought I'd provide a quick update for anyone thinking of doing the same...

It's been 3 months since I started the thread and put a small amount of the recommended 2 stroke oil in the diesel tank. 

immediately it was much quieter, engine noise noticeably. I could even turn the radio down as it seemed it was shouting at me now.

over time obviously I've gotten used to the new level of background noise and was thinking of doing it again to see if it made any further difference. I was hoping to wait 6 months so as to try and prevent any build up of oil in sensitive areas.. I'll do some more forum reading before adding any more to see what people 1yr + down the line are experiencing, but would like to see if I can push the mileage any further..

Car itself Is performing fine. just flew through an MOT with almost untraceable results showing on the emissions report. No sign of injector issues, fuel pump issues or (touch wood) any other issues.. :thumbup:

again, if you chose to do this to your car, your mileage may vary and you may cause more issues than you resolve, you've been warned


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