Hi Guys, would you recommend using a fuel additive on a regular basis or not ?

Cheers

Paul

I'm sure I have read it somewhere that it plays havoc with the DPF and is not worth it. I'm sure an expert will be along shortly to give you some better information.

Given the quality of modern fuels (and the close tolerances all engines are made to these days), I'd put the extra money in a jar and have a night out with it once a year.  You'd get more benefit from it.

You'll probably invalidate the warranty if you do.

Considering it does say in the manual NOT to use fuel additives...

just to reiterate previous posts when I purchased mine the salesman on collection stated not to use additives or premium diesel fuels just regular old diesel from the supermarket

DONT USE SUPERMARKET FUEL!!! Regular diesel from esso,bp or shell. Treat it to a premium tank once a month. No power difference on premium diesel but the cleansing agents will pay dividends in the longevity of the engine.

DONT USE SUPERMARKET FUEL!!! Regular diesel from esso,bp or shell.

Where do you think supermarket fuel comes from?

Different additives are added at the refinery Neil, depending on which forecourt the fuel is ending up on

Absolutely right! The base fuel is all the same. Even filled at the same dock. Depending on the company's tanker on the dock the additive recipe can be altered to suit.... Tesco lorry= basic additives. Shell lorry= better additives for standard fuel and complex mixture for nitro+.

Morrisons is the name that gets mentioned up this part of the country, A garage owner friend used to get cars in with lots of problems associated with fuel once Morrisons had opened a filling station in Morpeth, as a result I will not use their fuel

I tend to go for whoever has the cheapest fue and have used Tesco & ASDA without any noticeable effects on both my Company cars (25-30 K per year)and my own private cars

I used Tesco for the first 12 months after getting my O3, then switched to regular Shell and whilst the car ran fine on Tesco, it averages about 50 miles extra per tank on Shell, so the extra 2-3ppl is worth it as that costs about £1.20 per fill up but to go the extra 50 miles on Tesco fuel would cost about £5.50.

Strange how VAG recommends using no additives, yet the additives within Shell are supposed to be good. Personally, I notice no difference between Supermarket and branded, or 95RON & Super within my VRS TSI, and yes I have tried every fuel going multiple times. In fact I have run more Shell V-Power Nitro+ than anything else during the past 3-months and still notice no difference (I keep trying just in case) . I think that for the TSI engine it is all placebo and no medicine.

 

Also there is no measured in fuel economy for me. It just costs more.

You shouldn't notice any sort of performance difference with diesel especially in the short term 1-2 years it's as the engine gets much older and you get carbon deposits. The complex additives used in the premium diesel keep everything clean and working as it should. Modern Diesel injectors are marvels of engineering and have to do a really hard job with exact precision every time and they relay on their fuel for lubrication and cleaning. Put into perspective a petrol injector does 1 injection per 4stroke cycle. Some modern diesel injectors do 6!! Thinking of cost, a petrol injector maybe £40-80. A diesel injector £250+.

I'm not saying you have to use posh fuel. But in the long term the car will benefit from a tank full every so often.

I know this is a diesel debate, but I see no reason why what applies for petrol should not apply for diesel. After all, manufacturers design their engines to work at maximun efficient with existing fuel specificiations.

 

Here are the mpg results from my TSI engine using different fuels. Notice how Premium branded or Super unleaded make little difference to economy. I also feel no difference in performance, but of course I cannot see what damage each does (or not) to injectors and internals. However, my car will be handed back before the warranty expires so I don't really care about internal wear.

 

 

Overall

It tends to be supermarket filling stations you hear about in misfilling/contamination cases.

I know of people who have had cars knackered by supermarket stations...never heard of it happening in a branded station....though I am sure from time to time it probably does.

Branded stations I suspect tend to invest more in their forecourt equipment and tank maintenance.

Ironically...my company changed fuel card provider a little while back from Allstar (which could be used practically anywhere accepting debit cards) to Shell as they got a far better corporate deal but means I can only use my card in Shell, Esso and most Texaco garages....so I dont have the problem of chosing supermarket fuel stations as I cant use them anyway :-)

I know my wife buts any old ****e diesel in our Mk3 and it drives fine and returns expected economy.

Strange how VAG recommends using no additives, yet the additives within Shell are supposed to be good. Personally, I notice no difference between Supermarket and branded, or 95RON & Super within my VRS TSI, and yes I have tried every fuel going multiple times. In fact I have run more Shell V-Power Nitro+ than anything else during the past 3-months and still notice no difference (I keep trying just in case) . I think that for the TSI engine it is all placebo and no medicine.

Also there is no measured in fuel economy for me. It just costs more.

As others have said, I was referring to my O3 TDI, but would agree that in a TSI there is no or little performance or economy advantage, SWMBOs TSI can vouch for that, but having run it for over 6 years on mainly 95 Ron Tesco, it has developed a carbon build up in the inlet manifold and now misfires or flutters under gentle acceleration at approx 2k revs, it has only covered 36k miles. Some say that had we used higher octane fuel, the carbon build up would be less.

Edited 31 October, 201510 yr by Matt Pez

Cannot see that using a higher Octane fuel will reduce carbon build up.

If your wife's car is DI only then with low annual mileage and a lot short trips from cold and few good runs or a ragging when warm surely it is inevitable.

The aggressive use of EGR and crankcase recirc by manufacturers to reduce emissions would be a major contributor.

If you have dual instead and manifold injection then that is a slightly different story but I believe that manifold injection is mainly used during aggressive driving. Others would know more about that.

I am resigned to th fact that I will suffer the same problem with my 1.4tsi eventually.

Edited 31 October, 201510 yr by Gerrycan

As others have said, I was referring to my O3 TDI, but would agree that in a TSI there is no or little performance or economy advantage, SWMBOs TSI can vouch for that, but having run it for over 6 years on mainly 95 Ron Tesco, it has developed a carbon build up in the inlet manifold and now misfires or flutters under gentle acceleration at approx 2k revs, it has only covered 36k miles. Some say that had we used higher octane fuel, the carbon build up would be less.

Higher octane fuel would have made no difference because high-RON merely increases the point at which heat & compression causes pre-ignition. Your low mileage is more likely the cause of carbon build-up. Low mileage tends to marry with with short runs, and engines run richer whilst warming up. Richer mixes produce more carbon, and can clog cats, which in-turn can cause further internal carbon build up. Some fuels list carbon-reducing additives, but nobody really knows how effective they are, and most manufacturers advise against additives.

Edited 31 October, 201510 yr by Orville

As others have said, I was referring to my O3 TDI, but would agree that in a TSI there is no or little performance or economy advantage, SWMBOs TSI can vouch for that, but having run it for over 6 years on mainly 95 Ron Tesco, it has developed a carbon build up in the inlet manifold and now misfires or flutters under gentle acceleration at approx 2k revs, it has only covered 36k miles. Some say that had we used higher octane fuel, the carbon build up would be less.

The super fuels can make a difference power and economy wise on petrols. especially economy. I've experienced it and so have others.

If we are going to talk about petrol as well... It's worth saying that although some people may see some initial benefits from higher octane petrol (power is more often a placebo effect) to get the full benefit the engine management system has to learn over time that it can tune the settings as such to make use of the new fuel by monitoring the knock sensor and making tiny adjustments as the engines best performance is literally just before knock or pinking occurs. These adjustments and learning take time 4-5 tanks of the same quality fuel before the management system really knows it can use the higher fuel settings....the down side is that the system is very quick to 'retard' performance almost instant if a lower octane fuel is used as the engine will pink and set its straight back to safe settings to avoid damage. So any performance difference is more noticeable down rather than up!

I had a Leon Cupra R 225 it was a beast running shell v-power as the recommended fuel was 98ron meaning seat had programmed it to run best on higher octane fuel, older focus st's were as well I think. if I ran 95ron it felt flat but was perfectly fine to use as It had to be able to run on any standard pump petrol.

Bottom line is that performance related gains rely on how the engine management system works. economy gains are made by keeping the fuel system it peak condition. anyone can benefit from the cleansing properties of the premium petrol and diesel. Think of it as a spring clean for your fuel system.

I agree that unless the car is designed or modified to run on 98 octane then any perceived benefits are purely due due to the placebo affect.

I record my consumption as do others and could find no benefit at all during a few tanks of 98 on my 1.4tsi.

Similarly I cannot find an independent laboratory test proving otherwise nor is there any mention in Skoda manuals or claims by petrol manufacturers.

I remember the very old Shell TV adverts which 'proved' that you got substantially better mileage on a gallon of Shell petrol when they ran two 'identical' cars on different brands and the Shell powered car always went about 5 miles further. No truth in advertising laws then.

Cannot see that using a higher Octane fuel will reduce carbon build up.

If your wife's car is DI only then with low annual mileage and a lot short trips from cold and few good runs or a ragging when warm surely it is inevitable.

The aggressive use of EGR and crankcase recirc by manufacturers to reduce emissions would be a major contributor.

If you have dual instead and manifold injection then that is a slightly different story but I believe that manifold injection is mainly used during aggressive driving. Others would know more about that.

I am resigned to th fact that I will suffer the same problem with my 1.4tsi eventually.

 

I believe the latest EA888 v3 engines (1.8 & 2.0) have both direct and port injectors

 

Any one used  Wynns Direct Injection Power 3  or something like it ?

Edited 1 November, 201510 yr by bigjohn

Those engines do but I thought read somewhere that manifold injection only occurs during aggressive driving?

My view is that all after market additives are akin to 'snake oil'. To each their own though

I had a Leon Cupra R 225 it was a beast running shell v-power as the recommended fuel was 98ron meaning seat had programmed it to run best on higher octane fuel, older focus st's were as well I think. if I ran 95ron it felt flat but was perfectly fine to use as It had to be able to run on any standard pump petrol.

I also had a cupra r225 that was running stage 2. Initially it was setup to run on vpower but I ended up running it mostly on 95ron due to the mileage I ended up doing (76k miles in two years! ). Can't say there was really a noticeable difference and on a rolling road it was within a couple of bhp of other cupra r with same mods running 98 Ron. I also ran a mk2 fl vrs with stage 1 for 60k miles and again didn't notice a significant difference.