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July 21st, 2011, 10:43
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#1516
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Veteran Member
Join Date: Sep 2009
Location: Indianapolis
Fuel Economy: 41.7 mpg average, 95% suburban
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DPM, a member from N. Ireland, wrote this on a thread in the A-5 forum, last week or so http://forums.tdiclub.com/showthread...323508&page=3:
That's the way it is with CR systems of all brands, and the way it's been for the past ten years and more. We went through the same problems "last millennium" with the CP1 pumps here in Europe. The slightest sniff of adulterated fuel killed pumps, worn in-tank pumps killed pumps; dead pumps took out injectors, tanks full of metal swarf needed replaced etc etc.
Oddly tho, it isn't such a problem any more...
So it seems that Bosch should already know about these matters. (I wonder if the above havoc caused Europe to raise it's diesel fuel standards.)
__________________
2009 Jetta TDI, black, tan interior with black dash, DSG, 16" Wheels, Build date 11/08 -- Running on http://www.countrymark.com
47.8 mpg best tank, all interstate @ 70 mph ----- 76,000 miles on odometer
2004 Toyota Solara SLE V6 (wife's), 1979 Diesel Rabbit (RIP), 1981 VW Diesel Pickup (RIP), 1986 Jetta gasser (gone).
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July 21st, 2011, 10:47
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#1517
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veteran member
Join Date: Jun 2011
Location: 49er State
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Quote:
Originally Posted by aja8888
If I was a test engineer at Bosch, I would currently be dumping different substances (gasoline, additives, water, etc) into D2 to do bench test runs on the HPFP for root cause failure analysis....... Hey, that should have been done prior to 2009!. 
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And then you should add bits of shaving and metal to the fuel too, from a failed HPFP and bench test it to see what happens, with a timer on it. See how long it takes, Mean Time Between Failure.
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July 21st, 2011, 10:52
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#1518
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Veteran Member
Join Date: Apr 2003
Location: Charlotte, NC
Fuel Economy: 55 max / 44 avg on beetle ~37 on JSW
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Quote:
Originally Posted by aja8888
If I was a test engineer at Bosch, I would currently be dumping different substances (gasoline, additives, water, etc) into D2 to do bench test runs on the HPFP for root cause failure analysis....... Hey, that should have been done prior to 2009!. 
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Wasn't that part of the report posted somewhere back in the beginning? That's how we have "determined" that the D2 fuel in the states does not have a high enough lubricity rating (or scar rating). IIRC, the report was done by Bosch.
__________________
2010 silver/black JSW TDI with DSG, 2011 red Golf TDI with dsg, 2003 red/gray Passat 1.8l gasser
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July 21st, 2011, 11:20
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#1519
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Veteran Member
Join Date: Dec 2006
Location: MS
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Quote:
Originally Posted by oxford_guy
VW sanctions biodiesel up to B5, and all you need is 1-2% to get adequate lubricity.
You can add a quart of B100 to one tank of USLD if you don't have B1-B5 in your area.
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Quote:
Originally Posted by Harvieux
My post was not meant in any way, shape, or form to lash you. I was mainly referring to such claims as 32 oz. of gas claim along with fact that no one, TTBOMK, other than "possibly" VW or Bosch knows exactly why these pumps are failing. Later!
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Quote:
Originally Posted by securityguy
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I may just think too highly of myself. Sure always is a possibility.
Adequate lubricity? Adequate if no contaminates (gasoline, water) hits the pump. No reasonable margin of protection).
If 1 1/2 ounces of gasoline per gallon of diesel fuel was the limit in the 60s (?) with no turbo. That probably has not changed and even today 1 oz of gasoline per gallon is probably way too much. I might as well offer a thought about an amount. I really do / will not feel bad about being wrong. 16 oz of gasoline in my 13 gallon Isuzu diesel tank would be about the same ratio. The amount of gasoline was based on partial history.
If a small amount of lubricant helps the situation, why would not a small amount of drier hurt the situation. Makes sense to a feeble minded fellow from Mississippi.
VW has the engineers and computers to know. Would it be logical to think they do know? Yes??? Would it be logical to think thay are going to try and stay just above warranty mileages? I seriously doubt they will make a 500,000 mile pump.
Since we have not been told the answer, it is logical to me to try and arrive at the problems. I do not think everyone that belongs to tdiclub should know what is wrong, but there are several people way smarter than me that I listen to (both education and / or practical experience wise).
Industry is loading parts to the very limit of their capacity. VW appears to need a better coating on the HPFP roller holder. I might as well be proved wrong here as well. I do not think we should all hide in fear of being wrong. Wild eyed guessing is dangerous--I agree. But being afraid to think is just as dangerous.
As club members, all we can probably do is filtering and additives. I suggest we have at trying to do as much as possible. We should also try and encourage each other to arrive at a plan before warranty is gone for the now new CRs.
Shadetree LOL (laughing to keep from crying)
eddif
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July 21st, 2011, 11:21
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#1520
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Join Date: Aug 1998
Location: Whittier,CA-USA
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I also recall a post way back which specified that Bosch gave VWAG a choice of pumps to go into the final production and Bosch recommended a specific pump and VW's bean counters chose the cheap route. I don't know how credible this is but, it sure stuck in my head as a possibility knowing VW as we do, eh?  Later!
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July 21st, 2011, 15:33
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#1521
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Veteran Member
Join Date: Feb 2006
Location: NJ
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Quote:
Originally Posted by Harvieux
I also recall a post way back which specified that Bosch gave VWAG a choice of pumps to go into the final production and Bosch recommended a specific pump and VW's bean counters chose the cheap route. I don't know how credible this is but, it sure stuck in my head as a possibility knowing VW as we do, eh?  Later!
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It would be nice to see a copy of an internal memo like that.
__________________
"Drink the Kool-Aid" -Jim Jones
"Baa-baa-baa" -Sheep
Now, I drive more, worry less.
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July 21st, 2011, 16:37
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#1522
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Join Date: Aug 1998
Location: Whittier,CA-USA
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Quote:
Originally Posted by El Dobro
It would be nice to see a copy of an internal memo like that.
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Tell me about it! As intrusive as our govt. is to our citizens at this point, it would sure be nice if the NHTSA had such intrusive power to go into VW's internal dbase and weed out such possibilities. I would bet there are some smokin guns in them there archives, eh?  Later!
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July 27th, 2011, 00:49
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#1523
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Veteran Member
Join Date: Mar 2011
Location: Ohio
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Part of keeping us safe is keeping unpleasant information out of our hands.
Drive more, worry less!
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July 27th, 2011, 05:30
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#1524
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Veteran Member
Join Date: Dec 2006
Location: MS
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Quote:
Originally Posted by oxford_guy
Part of keeping us safe is keeping unpleasant information out of our hands.
Drive more, worry less!
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Keeping us safe. Hmm
Emergency training classes:
Your car has just gone in to limp mode - these are the 5 things to do .......
Your car has just lost all power - these are the 6 things to do......
I would think unpleasant as the preperation for disaster is; there is no way to Drive more and worry less. When you are driving a vehicle that tends to have major failures you need to be informed and trained for disaster.
The other option is that the cars are made more reliable so we do not have to discuss panic situations.
LOL
eddif
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July 28th, 2011, 08:25
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#1525
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Join Date: Aug 1998
Location: Whittier,CA-USA
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Quote:
Originally Posted by oxford_guy
Part of keeping us safe is keeping unpleasant information out of our hands.
Drive more, worry less!
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Yup, that's what Arthur Neville " Chamberlain" promoted after his 1938 meeting with Adolf ******.  Later!
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July 28th, 2011, 09:20
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#1526
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Veteran Member
Join Date: Jul 2004
Location: Middletown, Rhode Island
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"We will have robust high pressure fuel pumps in our time."
__________________
2013 Passat TDI SEL, DSG, Night Blue Metallic (hers)
2012 Volvo C30 T5, 6M, Chameleon Blue (mine)
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July 29th, 2011, 10:43
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#1527
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Veteran Member
Join Date: Sep 2009
Location: So. California
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Quote:
Originally Posted by oxford_guy
VW sanctions biodiesel up to B5, and all you need is 1-2% to get adequate lubricity.
You can add a quart of B100 to one tank of USLD if you don't have B1-B5 in your area.
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Before you jump on the biofuel bandwagen you might want to read this post taken from another TDI forum (Myturbodiesel.com). I knew there must be a reason VW does not 'overly' recommend biodiesel............here it it is:
Using biodiesel up to B100 with a 2009 or newer VW Jetta TDI, Golf TDI, or Audi A3 TDI
The newer common rail TDI engines (CRD) in VW Jetta TDI or other models with DPF will run as well on biodiesel as older TDI engines ran fine on biodiesel. However, using biodiesel has three main problems. During the post injection combustion, it can collect in the cylinder instead of vaporizing and raising the EGT to heat up the DPF, preventing normal active DPF regenerations. By not vaporizing, biodiesel works its way into the engine oil much more than diesel. Because biodiesel has a higher distillation and boiling point, once it's in the oil, it accumulates and dilutes the engine oil.
There's always greater engine oil dilution during a post combustion injection cycle but regular diesel can evaporate more easily than biodiesel out of the engine oil. Once it evaporates, it's recycled into the air intake by the crankcase ventilation system and consumed by the engine. Biodiesel accumulates because it doesn't evaporate as easily. At a 2008 biodiesel conference, a VW representative said the engine could tolerate up to 50% fuel mix in the oil but no more. (source) This level could be exceeded after 10,000 miles with just B5. B10 would definitely exceed this level.
Some possible solutions are to delete the DPF on your VW or Audi TDI or install a DPF bypass kit. The engine tuning must also be adjusted to account for the removal of post combustion injection of fuel and DPF removal. It might be possible to tune the post combustion injection to have bio produce the same results as regular diesel.
The future of DPF systems might substitute an extra injector in the exhaust to inject the post combustion fuel downstream of the engine instead of right in the engine cylinder. This type of system is required if the DPF is downstream of the Adblue or NOx catalyst. Modern systems which don't use post combustion injection at the engine use this type of injection. In fact, when TDI was first introduced to North America, the VW Passat TDI used a low pressure injector in the exhaust to burn up fuel in the catalyst. It was discontinued because it didn't work very well, see 1000q: VW Passat 5th injector for details. Technology has improved since 1994-1995 so it's possible this type of system might return. The main obstacle is additional complexity and cost vs. an extra squirt at the existing fuel injectors.
Trace metals in the biodiesel from processing can also accumulate and foul SCR catalysts. On Adblue equipped cars like the Touareg or Q7 TDI, (see below for a detailed system description), most contaminants will be trapped by the upstream DPF. The level of trace metals are also so small that the SCR should be more tolerant of contamination and last the "real" lifetime of the car, or over 400,000 miles.
For more basic information about biodiesel and VW, see 1000q: intro to biodiesel.
__________________
9/02/09 Build date.
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July 29th, 2011, 10:47
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#1528
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Veteran Member
Join Date: Sep 2001
Location: san antonio
Fuel Economy: Golf: 54/48/43.5 B4 Passat: 52/48.5/45 B5.5 Passat: 30 mpg mixed
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Dan-
The suggestion was to use up to 5% biodiesel. Nothing you shared from the other site would contradict that.
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July 29th, 2011, 10:51
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#1529
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Moderator at Large
Join Date: May 1999
Location: Canada
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July 29th, 2011, 12:43
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#1530
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Veteran Member
Join Date: Jan 2009
Location: Las Vegas, Nevada
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Wow! Thanks TDIMeister! It looks like I have plenty of reading for this weekend. You gotta love this place as a source of information.
Have Fun!
Don
__________________
2009 Jetta SportWagen TDI
Candy White/Anthracite
Build date: 01/16/09; Buy date: 02/09/09
Coveted Three Pedal Version, Big hole in roof
Dieselgeek Shortshifter & Panzer Plate (my favorite & my smartest mods)
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