VW Golf TDI and biodiesel

[Shelldrake]

I'm looking around for a turbo diesel and test drove a Golf today at McGraths Liverpool. Stamped across the inside of the fuel cap was "Do not use biodiesel". The salesman said it applied to all TDI models in Aust. and was because the engine was not designed to take it - I held my tongue of course, but really what's the problem VW has with biodiesel?

[gbrought]

Hi Shelldrake,

there are quite a few different threads on various manufacturers responses to use of BD in Australia. I'm yet to read a response that is even close to satisfying, and some are downright insulting.
Others who have had direct contact with a manufacturer may want to comment on their experience.

But the TD Golf is an example of a car that is allowed to run on biodiesel blend in Europe, but not at all here!
The best the manufacturers can do is mumble something about Australian standards, which may (only may) have ahd some truth to it once upon a time,
but increasingly is used as a convenient cop-out.

With some major oil companies already blending 2% BD in their dinodiesel (they don't have to say under 5%), this would make for an interesting conversation with the manufacturers...

Hopefully in time (and with continued lobbying) we will see less of this prohibition from the manufacturers.

cheers,

Geoff.

[Robert]

I've written to them several times and they have officially ignored me. I had planned on buying the new Golf next year, but I will now be getting the new Mazda 626 that is releasing a diesel model this year. I loved the idea of the Golf and it WILL work with Biodiesel. The only problem is ignorance.

This issue will be addressed by a body that will represent the biodiesel industry in Australia soon. We, as a consumer group can do our part by nagging manufacturers as hard as we can and trying to educate them.
The reason most manufacturers are shy of biodiesel here is that they think it is not widely commercially available, therefore users might put homebrew in their cars. The question of whether homebrew would meet spec or not is irrelevant, as it cannot be proved to be consistent. The real truth of the matter is that no manufacturer provides warranty for any kind of fuel.
The only question is will biodiesel cause parts to corrode or fail? The answer to this question is quite simple: NO. But to qualify it better if it is a new car, they will not be using components made from nitrile rubber, as the current Ultra Low Sulfur Diesel fuel that you buy will have problems with this (see this thread for more info) and therefore will also have no problem with biodiesel. There is some industry misinformation regarding corrosive qualities of vegetable oil on some components. The reason this is misinformation is that those tests were done on diesel mixed with unreacted straight vegetable oil. This is NOT biodiesel, yet many in the vehicle industry think it is.

Anyway, I'm rambling.

To sum up: I will hopefully soon have some better information for you all on an Australian Industry body to represent biodiesel and push for change with manufacturers. In the mean time, don't give into ignorance and do your own research. Hopefully, this will also rub off on local representatives of vehicle manufacturers.

[moonan]

Hi, this is a bit of a late response to this thread, I have been away for a month...
Anyway, my 5 cents worth:

There are a number of separate issues here, and based on my research into VW TDI issues both in the US and Europe as well as here, my comments on these issues are...

1. Australian dealers and car company reps generally talk out of ignorance, whether it is hteir own ignorance or corporately mandated ignorance. Robert and others have commented many times on the reasons for this. Hence the dealer's comment that no VW engines are designed to take biodiesel. This seems to be VW Australia's position irrespective of the position in europe (some VWs approved for bio - I will explain the "some" below) and the US (all VWs OK for B5 but NOT higher).

2. However, the thick plottens...
Any VW TDI with "NICHT FUR BIODIESEL" or the english "Do not use biodiesel" indicates that there is a DPF (diesel particulate filter) in the exhaust that has some chemical injected into it to react with the exhaust and reduce particulates, making diesel cleaner in polluted euro cities. The chemical apparently either doesn't work with biodiesel or reacts badly with it, but either way the vehicle doesn't meet whatever particulate standard with bio in this case (and VW withdraws any previous approval for use with high-concentrations of bio). I have read considerable discussion in the german "touareg-freunde" website regarding VW plans to add DPI technology to the "workhorse" 2.5l 5cyl TDI in Touaregs (my engine) that is otherwise approved for biodiesel in germany with no mods. My owners manual indicates that the V6 & V10 TDI engine options for the Touareg would preclude bio because of this DPI. See the thread on this site concerning the peugeot and this type of filter, for discussion of whether this is a real issue or just another furphy. Thus it may actually be the case that even in europe the current golf may indeed be "NICHT FUR BIODIESEL".

3. The other part of the dealer comment about "no VW engines are designed for biodiesel" actually relates to options that are available for euro-VWs to actually make them more bio-friendly, and he is essentially saying that these are not available in Australia. As far as I can work out, these mods are limited to heated fuel lines and (I think) a different fuel filter (to cope with changes from petro-diesel etc). My owners manual simply says that you should limit the use of bio in cold ambient and clean the fuel filter every 15k instead of 30k, and my VW is standard (but without DPF).

4. Anyway, none of the old issues of rubber components etc are applicable to these engines, there are no issues at all at or below B5.


cheers,

..Neil

[Robert]

Thanks Neil - very good info. It seems that we all need to get to the bottom of this particulate filter issue properly as at the moment we are unarmed against what is potentially just some more ignorance manifesting as the enemy of biodiesel again.

[John K]

In response to Moonan's comments about VW's plans to add particulate filters (DPF) to the 2.5 TDI engine as used in the Touraeg R5 and Transporter TDI I can confirm that my new Transporter was delivered last week with this system fitted.

To be fair I didn't specifically ask VW if this would be fitted, I just knew that the engine was bio compatible and planned to try some in the future.

Now I am wondering if this system can be easily removed, restoring the ability to use bio?

I suppose removing it would invalidate the warranty. Bugger.

Cheers,

John K

[DutchAussie]

In response to Moonan's comments about VW's plans to add particulate filters (DPF) to the 2.5 TDI engine as used in the Touraeg R5 and Transporter TDI I can confirm that my new Transporter was delivered last week with this system fitted.

To be fair I didn't specifically ask VW if this would be fitted, I just knew that the engine was bio compatible and planned to try some in the future.

Now I am wondering if this system can be easily removed, restoring the ability to use bio?

I suppose removing it would invalidate the warranty. Bugger.

Cheers,

John K

John,

our 2007 VW Caddy 1.9 L TDI engine runs like a dream on Biodiesel.
I have now done 7700 Km on anything up to 100% Biodiesel (from new) without any problems.
The only problem is that Biodiesel has a much higher viscosity then PetroDiesel and will give problems in cold weather. I run a 20% Biodiesel/ 80% Petrodiesl mix in the winter. (temperatures drop to about -5C where I live in SA).
When I start the engine I rum it at about 2000 rpm and wait for about 10 seconds when the engine speeds up and I know I can go without any problems.

I have been trying to find out about what is different with the European "heated" fuel system, as mentioned before in this forum, but have been unable to get information so far.

I would appreciate information, on the heated fuel system, if anyone can help.

[NewBioer]

Dutch,

does your Caddy have DPF ?

[DutchAussie]

Dutch,

does your Caddy have DPF ?

Yes, I was told our VW Caddy has a DPF.
I will shortly get under the car and try and find it.

[UNSWSolar]

Just thought I would add my experience. I have been running my Golf TDI 1.9 on B100 for 10000km, no problems. I personally believe the no biodiesel policy is just to do with lack of balls. Oxidative stability in the PD engines might be an issue for Volkswagen, however what they don't realise is that the bio only polymerises on the injectors if it is bad quality fuel...not because of the high injection pressures.

Anyway, good luck picking the car. I love my TDI. Would buy another if I had the money.

Alex