68 Plate VRS 184 DSG etc..

 

Noticed that every time I run a tank of Sainsbury diesel my Octavia will regen 2-3 times a week (tank lasts about that long).

 

Does not happen if I use Esso or Texaco which are the other options on my commute.

 

I know there are generally 2 camps, the first that say supermarket fuel is the devil and others that say it makes no difference. But is there actually any reason why this may be happening? 

Fuel aside, and not knowing your driving habits, is it possible that the car isn't completing a regen fully, and then attempting to retry a couple of days later? 

 

Taking fuel in to account, there are strict limits on the minimum quality of fuel sold in this country, however each retailer will add their own additive packages to the fuel (is my understanding). So possibly the fuel is burning slightly cleaner thus not requiring as many regens.

 

I prefer a branded fuel in my own diesel (personal preference), over supermarket fuel, however I will make exceptions if I am doing long motorway drives (e.g. Bristol to Bangor and back the other week was done on just short of a tank of Sainsburys knowing that the car would complete a regen quite happily at motorway speeds). I usually put Esso or Shell (ultimate preference) in and don't notice the regens taking place unless I'm part way through when I get home (3 or 4 times a year I would guess).

 

Edit: Change made in line with comment two below. 

Edited 21 June, 20196 yr by J_D

@ExpiredInTransit - I'm thinking (lack of) fuel additive packs, based on actually knowing tanker drivers who all said that "yes every load is the same base stock; the difference is the additive packs that go into brand name, and not into supermarket fuel".

Edited 21 June, 20196 yr by KenONeill

2 minutes ago, J_D said:

there are strict limits on the minimum quality of fuel sold in this country,

Edit inline, bold.

Yeah, should've specified, I'll change it. Thanks though! 👍

Sainsbury's fuel is Re-branded BP fuel, better than Morrisons cr*p. << Opens can of worms

 

My 245 normally drinks Tesco's Finest and my second choice is Sainsbury's super unleaded.

 

 

 

Edited 21 June, 20196 yr by Auric Goldfinger

11 minutes ago, Auric Goldfinger said:

Sainsbury's fuel is Re-branded BP fuel, better than Morrisons cr*p. << Opens can of worms

When I filled my 1.4TSI with Morrisons cr*p unleaded earlier this year it threw several lambda faults, cleared them and went back to other suppliers - never had the problem since...

 

So beware not only Morrisons diesel but also their petrol

Can tell you right now, the only direct answer to your question will be biased opinions from armchair speculators - nobody will be able to tell you the actual reason.

 

What I'd be more concerned about is when you say there are more regenerations per tankful.  How many re-generations do you typically experience per tankful? If the car is going thru regeneration quite often then that suggests the fuel isn't your problem. Are you driving EXACTLY the same each week?

 

 

 

22 minutes ago, Auric Goldfinger said:

My 245 normally drinks Tesco's Finest and my second choice is Sainsbury's super unleaded.

 

 

 

 

If you're experiencing regenerations with super unleaded then there's defo something wrong. 😀

10 minutes ago, PetrolDave said:

When I filled my 1.4TSI with Morrisons cr*p unleaded earlier this year it threw several lambda faults, cleared them and went back to other suppliers - never had the problem since...

 

So beware not only Morrisons diesel but also their petrol

 

This is typical of the replies to expect. Not for a second saying that's incorrect and if other garages solve the problem great.

 

BUT

 

Everytime I pass a Morrisons, the fuel forecourt is full of cars. Now if their fuel was crap and kept throwing up issues, their forecourts would be empty.

 

Conclusion:  It might be your car that's the problem?

15 minutes ago, Scot5 said:

 

Everytime I pass a Morrisons, the fuel forecourt is full of cars. Now if their fuel was crap and kept throwing up issues, their forecourts would be empty.

 

Conclusion:  It might be your car that's the problem?

 

With respect to diesel vehicle only:

Older (non-DPF) cars are quite happy running on whatever you fancy tipping in the tank.  They will puff out the nasties and perform better or worse depending on the composition.  

As for more modern (DPF equipped) cars, someone once explained to me the issues they have with running biofuel which is also one of the things that Morrisons includes at higher quantities than the likes of Shell v-power.  I believe one of the side effects if greater particulate.  Not directly from burning biofuel, as I'm pretty sure it burns cleaner, but from the combination with the other fossil fuel and additives.  On paper the biofuel burns better but it lacks the lubricating properties of fossil fuels.  This may be a contributing factor.

 

TLDR:

People might not realise the damage they are doing as they don't care as long as the car goes when pedal pressed.

My car runs better* on posh diesel. * better = more miles per tank, cleaner (DPF blah blah blah), nicer to drive (subjective)

Source of fuel content advice is a university engineering doctor so might know some stuff about some stuff.

Edited 21 June, 20196 yr by MarkyG82

17 minutes ago, Scot5 said:

 

If you're experiencing regenerations with super unleaded then there's defo something wrong. 😀

 

Maybe not so wrong now though going forward eh?. Although I've not looked deeply into GPFs and their cycle, I know they differ from DPFs in that they aren't a storage filter so might not even have a regen cycle.

@ExpiredInTransit how long are your journeys and what is the average speed? My vrs tdi is able to do a passive regen on the way to work and back on the way home as it's getting up to temperature on the motorway.

 

I've only noticed an active regen when I've had potter about round the city in slow moving traffic.

Edited 21 June, 20196 yr by tunedude

53 minutes ago, Auric Goldfinger said:

 

My 245 normally drinks Tesco's Finest and my second choice is Sainsbury's super unleaded.

 

 

 

 

30 minutes ago, Scot5 said:

 

If you're experiencing regenerations with super unleaded then there's defo something wrong. 😀

 

The 245 has a GPF but I don't know if it actually does regens and how long the life time is................

54 minutes ago, Auric Goldfinger said:

Sainsbury's fuel is Re-branded BP fuel, better than Morrisons cr*p. << Opens can of worms

 

My 245 normally drinks Tesco's Finest and my second choice is Sainsbury's super unleaded.

 

 

 

 

This is wrong, I worked for BP for 9 years, they have shut or sold off their UK refineries years ago

 

The fuel will come from any one of a number of refineries, could even be one in Rotterdam etc,

 

The tanker loading points get the same base fuel EN228 etc  (this it what it is described as on the pump)

Additives are then blended in as tanker is filled, the additives are company specific

 

The other variable is the bio-fuel percentage (there is a max), and all UK pumps will be marked by September to show the biofuel

 

 

Mine normally triggers regens every 300 miles or so (sometimes a little more, sometimes a little less).

 

The best think I did was to buy a £12 bluetooth ODB2 dongle and £3.30 for he VAG DPF app, you can see exactly what the car's doing in terms of DPF regens.

 

If you interrupt a regen, it doesn't always pick up from where it left off depending how far it was through the cycle.  For example, I stopped driving when the soot was down to about 50% and it waited until it was around 90%+ to regen again.

 

Earlier this week it went into regen just before I arrived at work and the soot level had only got down to 87%, 20 mins (10 miles) into my journey home it went back into regen mode which completed when the soot level was <30%.

 

I don't think this has anything to do with the fuel you're using but more likely how the regen cycle is coinciding with your jouneys

7 minutes ago, Auric Goldfinger said:

 

 

The 245 has a GPF but I don't know if it actually does regens and how long the life time is................

 

GPFs are passive filters, they run hot enough to do it continuously

Completely different to a DPF which needs additional fuel for an occasional hot run to burn off the debris

1 hour ago, J_D said:

Fuel aside, and not knowing your driving habits, is it possible that the car isn't completing a regen fully, and then attempting to retry a couple of days later? 

 

Taking fuel in to account, there are strict limits on the minimum quality of fuel sold in this country, however each retailer will add their own additive packages to the fuel (is my understanding). So possibly the fuel is burning slightly cleaner thus not requiring as many regens.

 

I prefer a branded fuel in my own diesel (personal preference), over supermarket fuel, however I will make exceptions if I am doing long motorway drives (e.g. Bristol to Bangor and back the other week was done on just short of a tank of Sainsburys knowing that the car would complete a regen quite happily at motorway speeds). I usually put Esso or Shell (ultimate preference) in and don't notice the regens taking place unless I'm part way through when I get home (3 or 4 times a year I would guess).

 

Edit: Change made in line with comment two below. 

 

51 minutes ago, Scot5 said:

Can tell you right now, the only direct answer to your question will be biased opinions from armchair speculators - nobody will be able to tell you the actual reason.

 

What I'd be more concerned about is when you say there are more regenerations per tankful.  How many re-generations do you typically experience per tankful? If the car is going thru regeneration quite often then that suggests the fuel isn't your problem. Are you driving EXACTLY the same each week?

 

 

 

 

22 minutes ago, tunedude said:

@ExpiredInTransit how long are your journeys and what is the average speed? My vrs tdi is able to do a passive regen on the way to work and back on the way home as it's getting up to temperature on the motorway.

 

I've only noticed an active regen when I've had potter about round the city in slow moving traffic.

 

Thanks for the replies..

 

Driving habits - A road (national limit) commute 35m each way daily plus work motorway driving which varies distance wise. I don't tend to drive like miss daisy.

 

Typical regens - None that I've noticed while on other fuels. I've only noticed them after pulling up on my drive. How far or driving style doesn't seem to reduce the chance of regens.

 

I could be wrong in my conclusion that it's the fuel to be honest. Just seemed coincidental and wondered whether it was a known thing.

26 minutes ago, SurreyJohn said:

 

This is wrong, I worked for BP for 9 years, they have shut or sold off their UK refineries years ago

 

 

 

 

If you Google " Who makes Sainsbury's petrol t come up with " BP have been supplying Sainsbury's since 2004." 

10 minutes ago, Auric Goldfinger said:

 

If you Google " Who makes Sainsbury's petrol t come up with " BP have been supplying Sainsbury's since 2004." 

I wasn't aware that everything that Google replies was "proven beyond reasonable doubt".

2 minutes ago, Auric Goldfinger said:

 

If you Google " Who makes Sainsbury's petrol t come up with " BP have been supplying Sainsbury's since 2004." 

 

They have a long term supply contract, but that doesn't mean BP make the fuel, they buy it in as well, and from where varies depending on where you are around the country

 

Moving back on topic, what people call diesel fuel in UK is actually EN590 (look at the pump it will say EN590)

Specs of EN590 are below, over the years sulphur (the main lubricant) has been reduced (to cut sulphur dioxide gas and acid rain) and other additives for lubricity added by some brands, but they are not mandatory

Every batch will be lab tested to meet these specs, off spec batches will be mixed with one from another storage tank, so resultant mix is on spec

Clearly as some limits are min or max the actual fuel can vary (and it depends on the assay of the individual crudes used in refinery

 

You will also note that upto 7% can now be FAME (biofuel) or in plain English, parts of plants.  

You can always ask your retailer for percentage (it will be on their fuel delivery docket so they will have it, even if no one normally asks)

 

https://www.ipu.co.uk/en590/

4 hours ago, tunedude said:

@ExpiredInTransit how long are your journeys and what is the average speed? My vrs tdi is able to do a passive regen on the way to work and back on the way home as it's getting up to temperature on the motorway.

 

I've only noticed an active regen when I've had potter about round the city in slow moving traffic.

I am not really clear how a 'passive' regen is defined?

Those with the DPF app report that a regen operates at about 500+ deg C which is about double the normal temperature. 

A regen is pretty obvious in traffic as the revs are higher, the radiator cooling fan goes on high to control engine temperature and the smell of a very hot exhaust can permeate into the cabin.

Driving on a highway/motorway at around the 70mph speed limit would not be enough to bring the temperature anywhere near regen requirements so extra fuel still has to be pumped in to achieve the regen temperature, however the revs would be the same, the radiator fan would not have to come on and smells would be carried away, so the regen would not be obvious but is not passive.

I would imagine you would need to be travelling at autobahn speeds or be towing a heavy trailer up a hill to achieve a truly passive regeneration.

 

While I think that diesel fuel quality could be a factor in soot generation I would be surprised that where the minimum statutory standards for fuel quality are met there would actually be much difference in the soot levels for the various brands or marketing hyped 'premium' grades. If that was the case then manufacturers would have demanded that the real world emission tests should be conducted using a premium diesel fuel.

 

Going back to the good old days of diesel powered trucks without any DPF (many on the roads still here in Australia) most soot is belched out when the trucks are running under load, either during acceleration or at speed (100kph on our roads).

Extrapolating from the above I would expect most soot on our personal diesels to be generated when cold and when driven aggressively. Which then also suggests that a diesel driven moderately (over a reasonable distance) gains consumption benefits in two ways, from lower initial consumption and fewer regens.

 

Discuss...…  

Edited 21 June, 20196 yr by Gerrycan

1 minute ago, Gerrycan said:

I am not really clear how a 'passive' regen is defined?

Those with the DPF app report that a regen operates at about 500+ deg C which is about double the normal temperature. 

A regen is pretty obvious in traffic as the revs are higher, the radiator cooling fan goes on high to control engine temperature and the smell of a very hot exhaust can permeate into the cabin.

Driving on a highway/motorway at around the 70mph speed limit would not be enough to bring the temperature anywhere near regen requirements so extra fuel still has to be pumped in to achieve the regen temperature, however the revs would be the same, the radiator fan would not have to come on and smells would be carried away, so the regen would not be obvious but is not passive.

I would imagine you would need to be travelling at autobahn speeds or be towing a heavy trailer up a hill to achieve a truly passive regeneration.

 

While I think that diesel fuel quality could be a factor in soot generation I am would be surprised that where the minimum statutory standards for fuel quality are met there would actually be much difference in the soot levels for the various brands or marketing hyped 'higher' grades. If that was the case then manufacturers would have demanded that the real world emission tests should be conducted using a premium diesel fuel.

 

Going back to the good old days of diesel powered trucks without any DPF (many on the roads still here in Australia) most soot is belched out when the trucks are running under load, either during acceleration or at speed (100kph on our roads).

Extrapolating from the above I would expect most soot on our personal diesels to be generated when cold and when driven aggressively. Which then also suggests that a diesel driven moderately (over a reasonable distance) gains consumption benefits in two ways, from lower initial consumption and fewer regens.

 

Discuss...…  

 

Passive regen - the exhaust gases are hot enough for the DPF to do it's 'magic'

Active regen - the dpf is starting to get clogged and the car injects diesel into the exhaust system to get the 'magic' going, because the temperatures aren't getting high enough

 

That's as a simple explanation I hope. There's a bit more which goes on in the background, but let's not confuse said matter. 

4 minutes ago, tunedude said:

 

Passive regen - the exhaust gases are hot enough for the DPF to do it's 'magic'

Active regen - the dpf is starting to get clogged and the car injects diesel into the exhaust system to get the 'magic' going, because the temperatures aren't getting high enough

 

That's as a simple explanation I hope. There's a bit more which goes on in the background, but let's not confuse said matter. 

But is it possible to get a passive regen in the UK without getting a speeding ticket or towing a horse trailer up a long hill?

Just now, Gerrycan said:

But is it possible to get a passive regen in the UK without getting a speeding ticket or towing a horse trailer up a long hill?

 

Oh aye, it's easy. My car is happily doing them on my commute to and from work, 80 mile round trip. Sitting on the motorway doing 70mph for around 40 minutes in total gives plenty of time for heat to build up and the dpf to 'do it's thing' either home or work bound.

 

I've checked it doing it using VCDS and a screen recorder (couldn't fathom how to do it on VCDS) and when the engine and exhaust gas temperatures get up, the soot levels go down. From my house it's about 2 miles or so before I'm on the motorway and it only takes another 5 miles up the motorway before all temperatures are in the sweet spot.

 

In recent months, I've only noticed an active regen when I've been on leave and I've been going round town (20 - 40mph) on short trips to the gym and the shops. You know it's an active one because it smells like a tyre fire when you get out.