[Closed] Fuel Additives for Diesel cars: what do you use? 🤔

Did they say why you would need an additive?
Detergent to clean injectors??

None. Just use non-supermarket fuel, and the whizzy Shell/BP/whatever super fuel once every few fills.

@jimw - yeah, we've not long had it as our runaround. Runs well. Just had a full service and the system was pretty mucky - maybe a little maintenance neglect, over the years? Anyways, suggested an additive will further help clean etc. & prolong life of parts...

@Rich_s - yeah, I avoid cheap fuel but good shout re: the dearer, posh stuff. Does that effectively act as a 'cleaner' (additive), so to speak?

None.

I do use a couple of tanks of posh stuff diesel a couple of times a year, including before MOT.

Additive - none.
Fuel - cheapest supermarket.
Emissions test - pass every time.

If it's mucky the best thing you can do is to use it and service it again. That's what filters are for.

I use this twice a year:
https://www.powerenhancer.co.uk/archoil-ar6400-d-max-professional-diesel-engine-turbo-dpf-cat-cleaner-concentrate.html

I always use the highest grade diesel and never
supermarket fuel.

I had an 08 RAV4 SR180 which got gummed up everywhere due to short journeys and poor quality fuel. DPF’s and EGR along with other little nooks all clog nicely.

I now have a Jeep Cherokee diesel which I’m
a lot more careful with.

It will be my last diesel vehicle.

I use dipetane in my old diesel

Comes highly recommended on my VW groups

Dipetane DP001 1 ltr Fuel Additive Treatment for Improve Fuel Economy and Reduced Emissions https://www.amazon.co.uk/dp/B00BXK1JBA/ref=cm_sw_r_cp_api_glt_fabc_DWM6PJY6HE10HYXB28HB

Have been using 'posh' diesel almost exclusively in our CRV.

Wife thinks I'm a mug but I keep pointing out I'm doing it on the recommendation of our mechanic who surely only stands to profit if we gum our engine up with crap.

Anyway, no issues with engine, emissions or MOTs, and will hopefully keep the car limping along for as long as possible (or at least until the frame rusts out which will apparently be at or around next MOT time... ☹ )

I use this from Toolstation,
https://www.toolstation.com/fuel-treatment/p75916

EMpty into tank of diesel, warm up engine and go to a quiet straight road, accelerate hard in 2 or third and watch the sky turn black behind you, do 50 miles and repeat, the harsh aceleration, engine will run quiet and smoot as well as improved acceleration use every few thousand miles.

Have used Redex, for diesels and doesnt do much.

Finest Yorkshire additive

Castrol Power 1 2T

I have been using this 2T motor oil as petrol additive to my Toyota Corolla 2005 Automatic for more than 10 years now every time I fueled up to 3/4 tank full. I just add 200ml or sometimes more to it.

Engine is very quiet and no issue whatsover.

My friend has a RAV4 and Prado in the far east; and he adds 2T to the petrol/diesel as well. Been doing so for nearly 30 years now. No issue whatsoever and he was a boy racer mechanic before.

None, never have. Speaking as an ex filling station owner & ex motor mechanic.

My 2001 Passat did 141k while I had I’d on supermarket fuel, without a problem & my current Mondeo has done around 90k on Morrison’s diesel, all without additives.

There were some threads on here about Optimax a few years back which might be worth digging out. I think the long and short of it was that the additives you manually add to the tank do pretty much the same as the decent stuff from a "main brand" petrol station. Do some sums and work out the cost difference.

Pretty sure someone worked in a refinery and said to definitely NOT use morrisons as they buy effectively the bottom of the tanks.

Also - with that age of engine I'd be doing a racing tune up. Decent fuel in, get it warm, onto a quiet motorway, 2.5k rpm for 20 minutes (use of 5th or 4th a good idea!) Clear all the crap out.

I know in all the diesels I've ever had (all company cars) they have all sounded less "clattery" on shell or bp than supermarket. And optimax does the same but with a little more "go".

YMMV.

BG244 from time to time has restored some fuel economy to diesels I've had.

Old works Transit used to get the odd splash of unleaded. Occasionally we would put the posh stuff in which meant the side exit exhaust would no longer hide the roads centre line in the mirror. Used to get 3 MoT before it would need injectors recon or replaced.

A bit of 2-EHN improved fuel economy for me.

Pretty sure someone worked in a refinery and said to definitely NOT use morrisons as they buy effectively the bottom of the tanks.

Pretty sure this is bollox...fuels have to meet certain standards and couldn't be sold if they didn't.

I used about a 20% unleaded mix about 10 years ago after a fuelling f_up. Fired quite a bit of crap out of the exhaust for a while after that, and it's been fine for the following 80,000 miles.

Pretty sure this is bollox…fuels have to meet certain standards and couldn’t be sold if they didn’t.

Pretty much this.
Diesel engines are the wrong engines for most people. Adding an additive isn’t going to change that.
Short journeys, not getting the engine up to temp (and that’s not just seeing the temp gauge move a bit) is shite for an engine and really shite for a diesel.
I’ve run predominantly diesels for years as my min commute it 36 miles each way to my office, with longer at least once mid-week.
Additives are either trying to mask an underlying issues like short journeys or snake oil.

Best things for an engine is being used normally/properly. That’s low rpm until up to proper temp. Then don’t let it labour when driving, use the revs &that’s not bouncing of the limiter in ever gear, but giving it a bit of throttle ain’t a sin either.

I do 16k a year at the moment, but was doing 30+ in previous roles. Use whatever diesel is convenient (whether big brand or supermarket) and not had an issue. Currently run 40 vehicle fleet and not one has had diesel issues (they suffer idiot issues, but haven’t found an additive for that, not that HR will allow anyway)

I dilute half a tank of supermarket diesel, 50/50 with supermarket diesel.

Pretty sure someone worked in a refinery and said to definitely NOT use morrisons as they buy effectively the bottom of the tanks.

Worked in the canteen or the security gate?

It's going to be bollocks if you think about it. The outlet of the tank is a floating arm* so it's always the top of the tank, and you don't run the tank empty to avoid landing the floating roofs legs unesseceraly because that will then draw air in and cause headaches**.

*and if the tank isn't fitted with a floating arm then the suction will be well above the water level in the bottom of the tank.

**and if you're unlucky explosions.

Plenty of anecdotal and truthful stuff here.

https://singletrackmag.com/forum/topic/shell-v-power-or-bp-ultimate-diesel-fuel-does-it-make-any-difference/

The Morrisons thing was something to do with them buying fuel on the spot market rather than futures. So they aren't able to pick and choose the quality of the packs - fuel quality is variable above and around the minimum standards. Let's face it, if you look for stories of contaminated fuel, morrisons is pretty much top of the list.

Modern diesel engines will burn any old shite..

Dont wate money on "additives" once a week wring its neck for a mile or two.

I used to add 2stroke oil to my Transit but now it's nearing the end of its life due to rust I don't bother. It's deffo smoother and quieter on 2stroke.

With my 190k mile VW PD engine I squirt MrMuscle oven cleaner into the turbo vane actuator side of the turbo when it starts sticking and throwing codes.

Modern diesel engines will burn any old shite..

Dont wate money on “additives” once a week wring its neck for a mile or two.

this.

We both drove Mercedes diesels from 2005 to 2018. One did mostly low speed, multiple very short journeys day after day with a ~monthly 200+ mile outing. The other did mostly short high speed journeys with ~monthly 200+ mile outings.

used whatever fuel was cheapest.

Is there any actual evidence for the supermarket diesel is shite thing?

My bet would be that it's viral marketing by branded stations.

Modern diesel engines will burn any old shite..

that's not really true. The older the diesel the less fussy it is about fuel quality.

Modern high pressure fuel pumps and injectors are fairly fussy.

We had a transit that would surge at idle on Morrisons fuel. But never on any other fuel

Can someone explain the difference between “super market fuel” and fuel from (I guess) BP/Shell/Esso/whatever?

In my head the quality would be regulated so it’d all be the same.

5 mins on Google will tell you that there is no difference between the base fuel..only the additives chucked in the more expensive brands which may, or may not, be good.

And anecdotal stories about contamination are likely to be how individual stations store it

Mrs D's car had some injector problems. Took it to a specialist who took them out and measured them, cleaned them and put them back in.

They said they were all fine but around £200 each to replace.

They advised me to use the really good fuel and to stop using supermarket fuel which we've done and haven't had any errors until this week. Turns out she filled up at a supermarket last time.

No idea if it's a coincidence but it will have the good stuff next time and be taken for a good run.

My vw t5 I've had for 12 years gets what ever is available but I add redex when ever I find it on offer at half price. No idea if it works but its cheap enough (when on offer)

My van one year didn't get used much and failed an emissions test. My mechanic used some cleaner in it (think it was called revive)  reved it for a while and put an air freshener in to hide the smell, it was around £30. I think that did far more than any additive I've used over the years. The results on emissions was amazing before and after.

Word from my work (Scotland) is that locally Sainsburys, BP, Shell, Esso etc all buy same quality stuff directly from refinery. Other supermarkets buy from Murco who import, blend and store in tanks. Direct from refinery is more consistent quality.
This was a few years ago and I asked in reference to diesel freezing up in cold weather.

Can someone explain the difference between “super market fuel” and fuel from (I guess) BP/Shell/Esso/whatever?

Nothing. Its the same stuff. The 'crap' or 'dirty' supermarket fuel thing is a myth. Its just the fancy stuff from Shell et al has additives in. Its only a fiver a tank more expensive to put the better stuff so I use it all the time as I'm not a high mileage driver and the additives actually work...The additives keep the extremely expensive fuel pumps and injectors in good working order. Modern diesels wont burn any old crap...just the opposite. They've become horrendously complicated with lots of fancy and temperamental tech that comes with a similarly horrendous price tag should things go wrong and need replacing...fuel pump for a modern diesel engine....£5k.

putting decent fuel in is even more important if you do alot of short journeys. Yes the latest gen engines have ways to manage the build up of gunk in the system, but my approach is I want to give those systems as easier ride as possible because they are not 100% effective and very expensive if they need replacing.

Word from my work (Scotland) is that locally Sainsburys, BP, Shell, Esso etc all buy same quality stuff directly from refinery. Other supermarkets buy from Murco who import, blend and store in tanks. Direct from refinery is more consistent quality.

It will depend where in the country you are. But all the fuels will come.from the same place. No one's rich enough to want to ship it further by road than they have to.

I'm not even sure the additives are consistent. When I commuted to Teesside from Reading the Esso garages at each end had different branding/advertising (one claimed "double detergent").

And just because you're Scottish therefore like whisky based advertising, doesn't mean imported and blended fuel is any worse than that distilled on the banks of the river Clyde 😉

the fancy stuff from Shell et al has additives in. Its only a fiver a tank more expensive to put the better stuff so I use it all the time as I’m not a high mileage driver and the additives actually work…The additives keep the extremely expensive fuel pumps and injectors in good working order. Modern diesels wont burn any old crap…just the opposite. They’ve become horrendously complicated with lots of fancy and temperamental tech that comes with a similarly horrendous price tag should things go wrong and need replacing…fuel pump for a modern diesel engine….£5k.

I never have done in any of my diesel cars, 306 2006-7, Mondeoo 2007-2010 or two Transits 2012-present, supermarket fuel and non issues whatsoever.
I did have a petrol Hyundai fail an MOT on emissions in 2011, gave it a bottle of Redex and an Italian tune up and the it passed so they must do something I guess

My commute is a 31 mile journey, 30 of it is on the motorway, i do 18k miles a year, I’ve had several diesels, no problems with emissions.
I’ve only ever bought supermarket fuel.
But, my car gets thoroughly warm on virtually every journey.

https://www.asa.org.uk/rulings/bp-oil-uk-ltd-G16-1014902.html

The stuff that gets cleaned out, where does it go?
https://www.bicycling.com/news/a22864724/roll-coal-cyclist/

https://www.cyclinguk.org/article/fuming-air-pollution-and-cycling

I had an 08 RAV4 SR180 which got gummed up everywhere due to short journeys and poor quality fuel. DPF’s and EGR along with other little nooks all clog nicely.

It got gummed up because of your short journeys not your choice of fuel station.

I know some people swear by supermarket fuel and others swear at it. One of the mechanics I use has told me not to use it, others have said its fine.

As to fuel additives I'll dry and dig the article out but it was a fairly compelling argument not to use them in the basis the oil companies know how to make fuel that does what its suppose to do and they can end up causing more issues than they fix.

All that said I tend to avoid supermarket fuel just because and every 3rd or 4th tank I'll treat the car to some premium diesel. I get a couple of good runs in a week at the moment too which I'm sure helps 🙂

Re: the stuff in Patons googling.

The BP adverts assume a "dirty" engine. For a petrol engine that's slightly misleading as the incoming petrol naturally cleans the inlet. I suppose the EGR might not help, but it's not like a diesel where significant amounts of crap can actually build up.

For their diesel they ran with a deliberately dirty fuel that just met the standard as you're trying to create a dirty injector (something petrol engines generally don't suffer unless direct injection).

And:

The stuff that gets cleaned out, where does it go?

"Rolling coal", removing DPFs and re-mapping are a separate problem done by selfish ****s.

i do 18k miles a year, I’ve had several diesels, no problems with emissions.
I’ve only ever bought supermarket fuel.
But, my car gets thoroughly warm

This
This
This

It got gummed up because of your short journeys not your choice of fuel station.

And this.

Buy the right tool for the job. You wouldn’t do a WC DH run on your road bike and you wouldn’t enter a tt on a something with 8” travel front and rear.
Don’t run round town stop start, never getting up to temp in a diesel, but if you are stomping up and down the motorway then get one.

And just because you’re Scottish therefore like whisky based advertising, doesn’t mean imported and blended fuel is any worse than that distilled on the banks of the river Clyde

I use supermarket fuel on my works van but only the finest diesel aged in sherry casks for my personal car.

Some old comments around fuel quality will have come from me.

Q1. All base fuel is the same.
Well yes and no. The specification is sufficiently wide enough to allow a number of "grades" to be on the market at the same time. You also need to consider the impact of the "bio " bit, what is it?

Q2. Biodiesel is all the same, no?
No, Def not. Most supermarkets are buying from major distributors who are working on very low margins, they are predominantly using used oils. I've seen many samples in the field that do not comply. Used oils in diesels can cause major issues in the sump with sludging. They will also Coke injectors.

Q3. Will additives work?
Yes, they can but with extreme caution. Over-dosing additives is more detrimental, and as most motorists have the view that more = better, they inadvertently end up bonking the engine by causing high amount of gumming material and possibly metallic compounds to the fuel. There is a reason why major oil companies spent a shed load of money developing fuels with the right additives, it's to avoid warranty claims.

Q3. Do supermarkets use additives?
Some do, but Morrisons is notorious for not. Quite simply you cannot run new vehicles in additive free fuel these days, especially if they contain bio, and/or constant short journeys.

Q4. Is UK refinery fuel the same as imports?
Yes and no. Depends on the crude slate as well as how the units are run. Everyone still blends at some point, it's just to what degree they do it to meet spec. The UK quality of fuel changes massively from North to South, sometimes for the better, sometimes worse. Do not for one moment think that every litre of fuel on the market is according to spec.

To put this simple, saying all diesel (and petrol) is the same as it has to meet a standard is like saying all German wheat beer is the same as it has to use the same ingredients- they do, but yeasts and crops differ giving a different taste. The fuel in this instance performance very differently.

Thats only a small snippet. There is plenty of here say with fuels, but I would not take anything you read in the press or on a number of forums as accurate, unless it's from those working in the industry..

Just on the Scottish thing.

Due to strategic importance, there are certain waivers given for what fuel must /mUST not be used. This also applies to other more remote locations.

@sui, that's really interesting. What fuel do you buy for your car having inside information? What fuel do you avoid? Morrisons?

Can you share some links to the Morrisons thing?

I stick with the majors, such as BP ,Esso and Shell. There is no public data about who uses what add packs etc as it's commercially very sensitive.. how do I know... Very expensive chemistry sets!

I chucked 25L of Esso Supreme Diesel in my 151K mile 11 year old 5er today at an eye-watering £1.54.9 per litre. Is it worth the 13ppl over normal Esso diesel? Is there a real advantage to using branded fuel over supermarket fuel? I don't mind paying a few ppl extra if it's worth it.

I usually fill up with whatever is cheapest and try to keep an eye on the garages I pass on a regular basis but the majority of fill ups were at Morrisons because it's the cheapest for miles. Using a different route to FoD to avoid the M5 I happened across a BP that was cheaper than Morrisions so topped the tank off with their standard diesel.

Is it worth the 13ppl over normal Esso diesel? Is there a real advantage to using branded fuel over supermarket fuel? I don’t mind paying a few ppl extra if it’s worth it.

Everyone has thier own view on this.

I find that in MPG only, it's an increase in cost.

I tend to fling a couple of tanks through before MOT, and I've never had emissions fail.

It does make the car feel more responsive, and going through two tanks does have a lasting effect in mpg terms in my car.

Arw folk still spouting this supermarket fuel drivel? 🤣