2011 JSW >B5 Diesel

[widm]

I live in Pennsylvania. From what I've been reading about the benefits of biodiesel for lubricity etc...I feel lucky that this state mandates B5 diesel. I feel very concerned about the future though because my VW owner's manual states not to use greater than B5 in my car (2011 Sportwagen). This PA mandate states the biodiesel percentage is to increase up to B20 as production of biodiesel increases up over time. I don't want to hurt my car and I certainly don't want to void my warranty. What are everyone's thoughts on the issue?

http://www.biodieselmagazine.com/art...to-take-effect

[chittychittybangbang]

IMHO, if VW's car cannot reliably sell a car in PA with diesel that the average and reasonable owner would buy, they don't meet the standard for merchantability and should cover any repair costs, even out of warranty. I wonder if HPFP problems are less in PA due to B5.

[widm]

Originally Posted by chittychittybangbang

IMHO, if VW's car cannot reliably sell a car in PA with diesel that the average and reasonable owner would buy, they don't meet the standard for merchantability and should cover any repair costs, even out of warranty. I wonder if HPFP problems are less in PA due to B5.

When you say "they don't meet the standard...", are you referring to VW?

Obviously this doesn't speak for the entire state of PA but my local dealership the self proclaimed "2nd largest TDI dealer in the country" allegedly hasn't had any claims on the HPFP. I asked about the reported HPFP failures and the sales guy stated he'd heard about it the failures but they hadn't received any instances/reports of it in their service center. Now, take that with a grain of salt from a guy trying to sell me a car.

[chittychittybangbang]

Yes, you can't sell a car if fuel can't be used in it. Even if a manufacturer includes a note or disclaimer there are still product standards. A lawyer could give you a technical answer.

The problem with greater than B5 is engine oil dilution. The main difference between the new TDI and older TDI is the post injection combustion. During a DPF regen active cycle, a little bit of fuel is injected after the regular fuel injections. Because of the properties of biodiesel, some more ends up on the cylinder walls and washed into the crankcase. Once there, it evaporates slower than diesel and therefore accumulates. If the fuel is B5, over time the percentage of fuel in the crankcase that is biodiesel goes from about 5% to 10% during a normal oil change interval. The concern is that over B5 lets bio accumulate faster. As an example, B20 might accumulate from 20% bio in the crankcase fuel to 50% bio in the fuel which is over VW's limits.

You can read more about it in the DPF article in the FAQ section. And I know who sold you your TDI

[widm]

Perfect, thanks for the explanation. I thought you might guess where I got my TDI.

[HigherRPM]

Is there anyway to disable the DPF regen active cycle via the ECU this feature and what is the ultimate harm in doing so?

[chittychittybangbang]

Originally Posted by HigherRPM

Is there anyway to disable the DPF regen active cycle via the ECU this feature and what is the ultimate harm in doing so?

Yes. I am not aware of any DPF bypass or DPF delete tunes for the VW TDI or Audi TDI. There are some in Europe but the tunes are slightly different for North America. Obviously they are illegal. However, the DPF would clog up so removal of the DPF and rest of the exhaust is required. It would certainly increase power and mileage but emissions would also go up dramatically. Ultimate harm = human well being since untreated exhaust of any kind is bad. Many states also have inspections.

[HigherRPM]

Thanks for the reply... I have heard other ways of dealing with the DPF is to spray with some form of solvent (urea?) I would hope that the companies building diesels for sale would realize that a move to higher bio blends (B20) is on the horizon. I've been using B20 in a 2008 6.0 Ford Van since day one with no ill effects. The company I work for has a fleet of delivery trucks running B20 for over 5 years with no issues.

[chittychittybangbang]

Not exactly, the DPF is only for particulates. They couldn't use them until the government required ultra low sulfur diesel because otherwise it would clog the filter.

Urea is for NOx. NOx is made under high temps with free oxygen. Diesels run lean. EGR helps lower NOx. The Jetta is light enough to not require it. The Passat and larger cars/engines use urea with a special catalyst to break down nox.

IMHO, the best solution is to have an extra injector for post injection combustion- no worries about fuel in the crankcase or biodiesel. However, this adds cost. Urea is nice because it greatly simplifies the exhaust system and isn't too expensive.

[Scratcher]

Originally Posted by chittychittybangbang

Yes, you can't sell a car if fuel can't be used in it. Even if a manufacturer includes a note or disclaimer there are still product standards. A lawyer could give you a technical answer.

The problem with greater than B5 is engine oil dilution. The main difference between the new TDI and older TDI is the post injection combustion. During a DPF regen active cycle, a little bit of fuel is injected after the regular fuel injections. Because of the properties of biodiesel, some more ends up on the cylinder walls and washed into the crankcase. Once there, it evaporates slower than diesel and therefore accumulates. If the fuel is B5, over time the percentage of fuel in the crankcase that is biodiesel goes from about 5% to 10% during a normal oil change interval. The concern is that over B5 lets bio accumulate faster. As an example, B20 might accumulate from 20% bio in the crankcase fuel to 50% bio in the fuel which is over VW's limits.

You can read more about it in the DPF article in the FAQ section. And I know who sold you your TDI

Wouldn't oil analysis balance this out?