Hello!

 

Ive driven my "new" car for about three weeks now, and I've filled er up two times. Both times I landed on 39Mpg (not USA mpg), this translates to 0,71L/Mil in Sweden. 

When looking at the MFD its behaving very irratic. Sometimes on a straight road it does 0,35. And more often it does in the region of 0,6-0,8. The funny thing: It's me driving at 80km/h.... I would expect theese numbers to show when driving around at 110+ km/h. 

 

I have a Volvo v50 which had alot of faults with the particulate cleaning system. The cleaning process is helped by a additive that gets injected at every full tank. I think the former owner neglected doing the refill for the additive. And the DPF was damaged. I had constant regeneration all the time, by the second it was done - it just started with a whole new cycle. And consumption wise it shot through the roof, 0,9L/Mil ! Outrageous for a small diesel car. Anyhow, after alot of faultsearching from the dealers side we got it working, by fixing the additive and installing a new DPF. All free of charge ofc! 

 

I wonder if I have the same fault with this one? My Octavia from 2007 2.0TDI BMM engine. I noticed today when I was driving home and kept my OBDeleven plugged in, that the temperature in the exhaust was between 250-400 degrees Celsius. And when it ran great considering fuel economy the temperature was always on the lower side. Ofc this will be varying when driving uphill etc, but I'm wondering if theres any correlation between high temperatures and regenerating? How do these cars regenerate the DPF? 

 

Is there anything I can monitor through OBDeleven that can be of use? Can I check soot level in the DPF? I've tried cycling through the channels, but I only get data, not a description on what it is :(

 

What could effect mpg? 

Turbo?

Cam timing?

DPF fault?

 

Thanks

I've done a few observations today when driving from work. When the motor is still heating up there's much better mpg. I was seeing between 55-70mpg when doing 90km/h. When it reaches operating temperature the consumption goes up.

 

When driving at 63-65km/h there's a great increase in mpg.. I get around 80mpg when doing between 60-65 and 35-47 when doing 70-90... When engine is WARM.

 

This leads me to the DPF. It feels like when motor gets hot enough a criteria is met and the regenerating starts. And it stops when driving between 60-65km/h. 

 

Does anyone know if there's something that breaks often in the particulate cleaning system? Like a pressure sensor or something? Can I diagnose a dpf pressure sensor?

Pressure sensors on the BMM have been known to give way - check for the US made one  at the back of the block top left fastened to a bracket by the EGR (if I recall correctly).  If it's Malaysian made it's probably OK.

2 hours ago, skomaz said:

Pressure sensors on the BMM have been known to give way - check for the US made one  at the back of the block top left fastened to a bracket by the EGR (if I recall correctly).  If it's Malaysian made it's probably OK.

My US pressure sensor passed away at 150k miles bit it was marked by a fault light on the dashboard.

I don't have any fault codes :/ I think I'm at 140k miles that's 240 000km. Is there any way to measure it? Or monitor in OBDeleven?

Today on the way home the car had good mpg all way home, strange... 

 

I'm currently using HVO100 diesel, I've read that it produces much less soot and that the soot is more easily combusted. The Cetane number is also higher than standard diesel, thinks it's around 72.

 

This is a translation from Google:

 

HVO 100 Use HVO100 ä is a renewable diesel fuel mainly for diesel engines in heavy vehicles but also for smaller dieselfordon. benefits HVO100 is a diesel product that combines technical and environmental performance on a very high level good way. The renewable energy of the raw materials drastically reduces CO2 and emissions at the same time as the product has properties like fossil diesel or better. For example, the product is very good cold performance, extremely high cetals, storage stability and not sensitive to microbial growth. Usually, no extra service measures are required on the vehicle when using the HVO100. Since This diesel burns extra clean, which allows you to extend service intervals in some cases. First check the engine manufacturer's specifications. Characteristics The chemical structure of the HVO (Hydrotreted vegetable oil) product is hydrocarbon compounds which means that the product can be described as a copy of ordinary fossil diesel. It is miscible with All diesel engines that are on the market that meet the standard SS-EN 590 and SS 155435. HVO100 is made up of 100% renewable HVO diesel with lubricating additives that provide good quality lubrication in fuel pump and fuel system. The energy content is somewhat smaller compared to MK1 diesel but the HVO100 is very high cetantal that causes it to burn more efficiently and thus compensate itself with one more effective combustion process. At constant low power output, consumption is therefore comparable with MK1 diesel but at least slightly higher. The more efficient and cleaner combustion gives less engine and cleaning systems, such as ex affects particle filters with improved service life. HVO100 is approved according to EN 15940 and ASTM D975 as most engine manufacturers on the heavy side but before the new standard is fully implemented, we recommend that you always Requires a documented approval from the engine manufacturer before using HVO100. The same applies also to smaller diesel engines in eg passenger cars. Environmental Performance The raw material for HVO100 is renewable from plant kingdom or offal (not from palm oil) which results in up to 90% CO2 and reduction of greenhouse gases compared with fossil fuels Diesel. HVO100 also provides fewer particles, less cold start smoke and reduced emissions of NOx, CO, and HC, vary with different engines and purification systems. Work environmentally, the product should be handled in a similar manner to conventional fossil diesel.

Edited 9 November, 20187 yr by andreasw

Is HVO100 100% bio-diesel?

 

If so, you really shouldn't be using it. Skoda/VW state a maximum of 7% bio-diesel for use with your engine...

 

http://www.volkswagen.co.uk/assets/common/pdf/general/biodiesel.pdf

 

2 hours ago, langers2k said:

Is HVO100 100% bio-diesel?

 

If so, you really shouldn't be using it. Skoda/VW state a maximum of 7% bio-diesel for use with your engine...

 

http://www.volkswagen.co.uk/assets/common/pdf/general/biodiesel.pdf

 

It's a 100% bio diesel yes. But it's not made from RME. Heres a paper on a few different diesels:

 

https://www.sciencedirect.com/science/article/pii/S0960148116310436

 

Very interesting read! "Regeneration of diesel particulate filters: Effect of renewable fuels"

Edited 9 November, 20187 yr by andreasw

Found this video comparing the fossil diesel with hvo

 

 

You can clearly see the difference in soot 

 

Thats about as relevant to the internal combustion compression ignition cycle as those snake oil demonstrations of ignition boosters etc with spark plugs in open air.

Not found any obvious guidance from VW/Skoda about HVO.

 

Might be worth using 3-4 tanks of regular diesel to see if the MPG changes?

It's pretty new, and might only be available in Scandinavia. It's originally from Finland. I know vw Sweden is doing some testing with some of their new cars. PSA engine group has already given it the ok for their newer engines. Alot of truck and taxi companies are already using it 100%. 

 

People have commented that since they started using HVO their dpf regenerations have drastically reduced. When I read the "scientific" paper I linked previously it seems to back it up. 

 

I'll continue to drive with HVO and see if I can get any results. Pretty expensive fuel though £1,50 a litre  Thats £6,9 per gallon. Normal diesel is £1,36.