So I've been curious as to whether anyone has tried different diesels and found any evidence that the more expensive premium stuff gives better fuel economy (that actually offsets the extra cost) or is just generally better for the engine. 

 

What are peoples thoughts? 

I use shell regular topped up with millars. costs 2p a litre more, but the shell garage I use is 1p cheaper than the local supermarkets. My CR seems to run better for it and I'm getting a few mpg more, but that could be due to summer temperatures and it loosening up, though 1 other thing I've not noticed is any regens for the last few months.whether the millars is anything to do with it I can't say but it'll be good to know what others have found.

i've compared shell v-power to tesco diesel and i have gain 50 miles plus using v-power. just filled a tank of 47 litres of regular shell diesel and going to see if any difference compared with esso diesel. will let you know. normally get about 500 miles to 50 litres.

When I got my 1.6 diesel I tried most of the branded diesel fuels on offer. I found little benefit from the super-diesels. But I may have been mis-judging them.

 

Back in the summer was using my local garage - Esso - for fuel and the average mpg was around 50 - 55. I then ran short of fuel and filled up with Shell's new improved diesel. Very quickly the mpg dropped to 31! Fearing something very wrong I took the car to my local dealer. No problems just the change of fuel. I have been more careful sticking to one brand since.

 

I think the car is able to 'tune' itself to get the best from whatevery fuel you use. But it takes a tankful to reach that point if you change.

 

So, it might be worth trying a super-diesel but sticking with it. Since the range on a full tank is pretty good you shouldn't need to worry about running out provided you plan ahead and top up before leaving town. The performance on my car (105 hp engine)  is adequate so getting more power isn't of interest if it means more cost.

Last summer I used Shell V-power in my Octavia for 2000 miles/3 months to see what affect it had on economy. 

 

Compared to Shell fuel save Diesel, MPG was slightly lower on V-power (expected as it has slightly less kJ/Litre than normal diesel). However it does burn very cleanly, and I noticed a big reduction in smoke on my Non DPF equipped car.

 

I concluded that it is not worth spending the extra on V-power diesel. However the occasional tankful might be a good alternative to using injector cleaner additives in normal diesel.      

Edited 20 September, 201312 yr by booke23

The best thing that anyone wondering about it is, try for themselves.

They have a lifetime of driving to make the decision or assessment over.

 

They drive their car, or vehicles & they might all be different in the most efficiant or cost effective fuel for them,

they know how they drive and when.

Use the more expensive stuff for a period of time and use other stuff.

Consider the season or conditions changing,

Do it with Brimmed Tanks and note the litres used, prices paid, and mileages done.

 

It hardly matters what different fuels can do for others and other cars and engine types,

that is not relevant to your pocket or your car usage.

 

george

I consider premium diesels to be more of a marketing hype than anything else. I always fill my tank to the brim, and I've never noticed a significant change im mpg. That said, the engine does seem to run smoother, so I do the occasional premium tank, but mostly I fill whatever brand or no brand whenever and wherever I need it.  

sk4gw

You make a very good point about trying it for oneself. However, many people mention filling the tank to the brim. Is this better for some reason? I thought it ends up worse for fuel economy over time because you're effectively carrying extra weight. 

 

My second query is this, what cleaners and other things do people use. I'm quite new to the world of cars and keeping them healthy etc but beyond checking the oil, filling the gas tank and servicing I don't know what cleaning fluids and addatives it's advisable to run through the engine and when. 

 

For perspective, I've driven for 3 years, I'm 23, I'm on my second car ever which is a brand new Skoda Fabia. Bought 5 months ago this year, now with 5K miles on the clock. 

 

Thanks for all your great advice guys. 

Brimming helps you getting the fill to fill proper amount used, kind of hard to judge your fuel use without doing that, ie going by Reserve light coming on, after sticking in 20 litres...

(Half tank around 22kg so full tank an extra 22kg, about the same as a spare wheel and jack, or a bag or 2 of shopping.)

 

Really you would mostly be doing it when going to do a long run,

if you are only doing short cold start runs, i doubt the difference in weight between a full and half tank will make much difference,

pulling into the service station and waiting with the engine running  twice or 3 times more often might use you more fuel. 

 

If you want to stop the possibility of moisture in your fuel tank over the winter, even when it goes over to winter fuel you might want to keep the tank as full as often as you can, before parking up and leaving sitting anyway.(less of a void to get condensation between day and night temps.)

 

Re , Efficiant running,  I would run the Diesel & do oil changes and not spend more on additives. Clean Air Filters, & inline fuel filters.

Checking and adjusting your tyres to the weather and having them correct for the load carried in the car is free if you have a tyre pressure gauge 

and a pump. No point paying 20-50 pence at a Garage. (a  tight Scottish person.)

 

george

I seem to recall one of the motoring shows on TV did a Dyno test with the premium fuels and it concluded that it gave an extra 3-6 bhp on the Dyno run compared to each of their normal fuel, my own personal experience is that the premium didn't give any extra mpg but did run smoother as stated above, in comparison when  i used Tesco's, Asda or Morrisons pump P155 to branded fuel Shell, BP etc I did find that it returned me significantly less mpg, I generally stick to one brand now and I'm quite happy with it.

Edited 21 September, 201312 yr by Raymo

I always fill the Yeti with BP Ultimate, the only reason for this is double nectar points, simple as that. 

I'll try the premium fuel for a little bit. You mention about keeping the oil clean and new. I've had the car 5 months from new and it has done over 5k miles. Should I change the oil now or should I do it at the 10k/1year service as Skoda recommends? 

Change the oil at the service.

When I got my 1.6 diesel I tried most of the branded diesel fuels on offer. I found little benefit from the super-diesels. But I may have been mis-judging them.

 

Back in the summer was using my local garage - Esso - for fuel and the average mpg was around 50 - 55. I then ran short of fuel and filled up with Shell's new improved diesel. Very quickly the mpg dropped to 31! Fearing something very wrong I took the car to my local dealer. No problems just the change of fuel. I have been more careful sticking to one brand since.

 

I think the car is able to 'tune' itself to get the best from whatevery fuel you use. But it takes a tankful to reach that point if you change.

 

So, it might be worth trying a super-diesel but sticking with it. Since the range on a full tank is pretty good you shouldn't need to worry about running out provided you plan ahead and top up before leaving town. The performance on my car (105 hp engine)  is adequate so getting more power isn't of interest if it means more cost.

 

There is something in what you say SlowBloke. When an engine has not been run on the super diesel stuff before, you often do get a dip in consumption figures ie: less mpg on a temporary basis. The reason is the super diesel is often so effective at cleaning the engine internals and the fuel system, the engine doesn't run as efficiently the first couple of tankfuls. In fact, many complain the engine runs rougher when they first put something like V-power in for the first time. It's only the crud in the fuel system and on the injectors being cleaned off but it can alarm people at first. If you stick with it the engine nearly always ends up running better and giving better economy and power than the cheaper less cleaner fuels. It can take a couple of tankfuls though.

I have been running my car on Shell standard diesel for over a year. I put in Nitro+ entirely out of curiosity to see if it was any different. Filled it to the brim from the fuel warning light. The engine runs noticeably quieter but economy over the tank dropped from 42 to 39 mpg and it wasn't because I was giving it the beans. I just refilled it yesterday to see what the 2nd tank is like, then back to standard, most likely.

Can we have a separate section on forum for these threads, preferably with a "hide it" option? I'm not saying it isn't an interesting or useful discussion, the first time at least. But there seems to be a new thread covering exactly the same ground on a daily basis...

Not Daily in this section though.  Maybe just ignore the threads that do not interest you.

The post title clearly shows what the thread will be about, so hardly a surprise when you click to read it.

 

george

I'll try 3 tanks full of the same stuff and let you know how it goes! 

 

I searched in the Fabia forum section and didn't find a relevant thread so created my own. 

Premium diesels have (and some additives give) a higher cetane rating.

 

I believe this helps reduce initial combustion delay and so reduces (explosive) knocking which is due to delayed combustion. It runs smoother.

 

With some diesel engines geared so high and low revs being used to acheive high economy, this would, in theory, help.

I have tried both types and to be honest I have never been able to note a difference that comes anywhere near the extra expense and that's if a difference can even be measured. The only quantifiable thing I have ever been sure about is exactly how much more it costs at the pumps I know a lot of peeps on here swear by the more expensive stuff though

There is something in what you say SlowBloke. When an engine has not been run on the super diesel stuff before, you often do get a dip in consumption figures ie: less mpg on a temporary basis. The reason is the super diesel is often so effective at cleaning the engine internals and the fuel system, the engine doesn't run as efficiently the first couple of tankfuls. In fact, many complain the engine runs rougher when they first put something like V-power in for the first time. It's only the crud in the fuel system and on the injectors being cleaned off but it can alarm people at first. If you stick with it the engine nearly always ends up running better and giving better economy and power than the cheaper less cleaner fuels. It can take a couple of tankfuls though.

 

Not in my experience. I ran V power Diesel continuously for over three months and 7 tankfuls. The poorer MPG was constant.    

There are old simple diesels you can run on Vegetable Oil that costs £1 a litre from any place and that might give you the same MPG as Diesel would, or enough MPG to save money..

 **Do not go putting SVO or WVO in a Greenline though. or many other modern engines.**

 

Some engines will never benefit from running on Premium Diesel,

and others might get the extra 25 miles or more per tank, that will repay the extra £3.00 a tank full of premium cost you.

Or just feel like they run better.

 

Thats why only the driver that does their own checks in their vehicle can ever know if it works for them.

You have different Supermarkets fuel to use, then different Branded, then Premium Branded, 

& all the time in the world to try them out.

 

george