Diesel Additives - dixgas
I've had my first diesel for four months (Lexus IS 220d) . I see a lot of guys use diesel fuel additives, at the car first service I asked the service manager about using one, and he advised against it.

I would appreciate your thoughts.

Diesel Additives - FotheringtonThomas
I think he's right.
Diesel Additives - craig-pd130
I tried various additives (Stanadyne, Millers) and all the premium fuels (Ultimate / V-Power) in my previous Passat, and none made any difference to performance or economy.

I tend to use Shell as it's my nearest filling station, and it's no more expensive than any other local forecourt.
Diesel Additives - Roly93
I've used Millers Diesel Power Plus and lately Diesel Power Sport 4 in my cars which have all been either VW or Audi PD engined. My experience is that whilst both products 'smooth' the engine out a bit when cool or cold, they tend to not only make more smoke, but actually reduce my MPG or at the very least have no effect at all on MPG.
I cant speak for all designs of diesel engine, but I dont think these additives suit VaG PD engines, and as such are just a waste of money.

Edited by Roly93 on 04/04/2008 at 12:18

Diesel Additives - dixgas
Why I asked, was I tend to keep my cars for a while, and also I buy them with my own dosh, so I was looking to the long term care of the engine. as opposed to mpg/performance
So I sould be ok

Thanks Roly

Diesel Additives - daveyjp
I read a piece in Audi Driver magazine which suggested the use of a certain additive (can't remember which one) prevented build up of carbon on variable vane turbos as fitted to 2.0TDi units. This has been a cause of premature failure of the turbo.
Diesel Additives - LinuxGeek
I've become a big fan of Shell V-power diesel, it definitely has a very positive effect on my Mazda 323 2.0TD engine. Engine runs quitely and smoothly. The engine feels more responsive when driving in low gears round town but as far as MPG is concerned I don't think it has any effect on it but then I don't mind paying couple of quid extra for a full tank to enjoy more smoother ride for a week or so.
Diesel Additives - Mad Maxy
I used to use Millers Diesel Power Plus in my Golf MkIV GT TDI 110 in order to improve lubricity for the fuel pump. This was at a time when there was concern about the lack of good additives in a lot of fuel; these concerns seem to have receded now.

The filler on my 320d says 'NO ADDITIVES'. I have toyed with Millers Diesel Sport (or whatever they call it now) but am in no rush to try it - because probably it won't improve economy.

As I see it currently, a new engine that is well looked after and gets properly used, ie long runs to get it nice and warm, and some decent revving from time to time, will keep in good shape. If you've got something that's suffering a bit from not being 'looked after' (see above), then an additive may help improve performance and economy.

Maybe a tankful of V-Power or equivalent from time to time, plus some healthy revving, would be beneficial for any motor...

David J: How do you find the Lexus? I rather fancy one.

Edited by Mad Maxy on 04/04/2008 at 13:17

Diesel Additives - Red Baron
Nobody that I know uses additives in their cars' fuel.

Indeed my previous Alfa never got any in 150,000 miles. Then engine still started and ran brilliantly when I got rid.

Would you buy little cannisters of 'air' for yourself?
Diesel Additives - GroovyMucker
I tried V-Power in my Avensis (same engine as OP's) but found it made no appreciable difference to anything.

Diesel Additives - Armitage Shanks {p}
As I mentioned a couple of weeks ago, I managed to put 10 litres of petrol into my 65 litres Diesel tank. Oh Bother, I said, How distressing! I topped off with diesel and put in a mega dose of Millers. 700 Miles later the car is still running and I attribute this to either 1. A large helping of good luck or 2. A large helping of Millers! Whatever it does I do not think it harms your car/engine; equally it may have no positive effect either. The debate will probably continue.
Diesel Additives - Cheeky
AFter the EGR valve on my Jag estate clogged, I have have just put in a dose of Millers for the first time today. Will keep you posted on its effects.
Diesel Additives - Collos25
A quarter a pint of petrol would do exactly the same.
Diesel Additives - jc2
Most vehicle handbooks say "don't" but the dealers try to add it to a service(they make a fortune on it).
Diesel Additives - Alby Back
Waste of money in my opinion. To get the best out of a diesel you just need to give it a good "throat clearing" blast at maximum revs (with a warm engine of course) a couple of times a week. There is a longish uphill gradient near me with a 60mph limit. I just make sure I hang on in second up the hill for a few moments on a regular basis. Blows all the cobwebs out for a while. Runs sweet as a nut afterwards.
Diesel Additives - MikeTorque
You can feel the difference with BP Ultimate compared with standard diesel, it smooths & quietens the engine and improves performance.

Shell V power smooths the engine but isn't worth the additional price.

Millers Diesel Power Sport 4 added to standard diesel improves the smoothness & quietens the engine and improves performance.

Redex diesel helps a little with smoothness but is not as good overall as Millers.
Diesel Additives - Mad Maxy
You can feel the difference with BP Ultimate compared with standard diesel it smooths &
quietens the engine and improves performance.

Mike, these are pretty significant statements.

What car/engine do these judgments refer to?

What do you mean by 'smooths'? Less vibration?

What do you mean by improved performance? Better acceleration, better flexibility? More mpg? Tested and demonstrated, or just your subjective impressions?

As you might gather, I'm sceptical. (But actually, It'd be great if you could substantiate it all because I'd love to get more mpg out of my 320d.)
Diesel Additives - craig-pd130
As mentioned above, I tried a range of premium fuels and additives in my B5.5 Passat PD130 manual.

Although I thought I felt differences, the stopwatch and economy calculations didn't show anything that couldn't be explained by ambient temp / traffic conditions.

BUT that is only my findings, on one model of car.

What I would say is, I got my car at the same time Shell launched Diesel Extra at my local filling station. So in theory, the engine should never have experienced major carbon build up because the fuel would be keeping it clean!
Diesel Additives - FotheringtonThomas
As you might gather I'm sceptical. (But actually It'd be great if you could substantiate
it all because I'd love to get more mpg out of my 320d.)

Is there no independent research published on these admixtures, or even magazine review?
Diesel Additives - nortones2
The only "test" I've come across relates to USA products most of which are unavailable here: background re US lubricity standards, and Bosch presentation. tinyurl.com/4em3ps
The test results are to be found on another site: tinyurl.com/3ezow5

Some additives seemed to make potential wear worse than raw fuel.
Diesel Additives - davmal
There was a similar thread from 6 March, but the originator was talking specifically about Miller's.

In reply to that post I said that, as a user, I had contacted Miller's and asked for a copy of their research, or if it had been published. They gave details of where their research originated, but wouldn't share it.

I still use Miller's, something has improved my mpg. Maybe I'm driving more carefully. or maybe the Miller's works. Either way, with Miller's at £12 a bottle my overall costs are down. Admittedly there "could" be even greater savings to be had if I am using it needlessly, but I am happy with the situation.

I think it would be incredibly difficult to carry out "home grown" tests on this kind of product and to come out with definitive results, there are far too many variables. I just tried it and decided for myself.

The US military use a product called Oxyol in their fuels, the tests were carried out at the SWRI in the US, and obviously impressed the colonials, but I believe tests carried out in the UK were inconclusive.
Diesel Additives - L'escargot
Some drivers add petrol to diesel, or is it the other way round? ;-)
Diesel Additives - Armitage Shanks {p}
In pre-common rail diesles it was common for lorry drivers to add petrol to their diesel to prevent gelling in very cold weather. Remember the picture of drivers with bonfires of rolled up newspaper under their tanks on Shap Fell? (Helf and Safety Innit?). Nowadays it isn't so cold and the fuel has anti- gelling additives in it.
Diesel Additives - AlanGowdy
I tried Shell V-power and it made the engine sound coarser and noisier with no discernible improvement to performance or economy. Went back to the normal stuff and it lost the roughness. I haven't tried the BP equivalent but suspect the result would be similar.
Diesel Additives - dixgas
Hi Maxy

I've had the Lexus for 4 months and so far I'm still looking forward to driving it, I got the SE model with has the leather heated seats which are very good. The gear box takes some geting use to (to big step between 2 and 3 see HJ review) but other than that I'm very taken with it.
I also got the multimedia option (£2700) but really very good, all the toys (satnav ac dvd/cd bluetooth) are controled from a 7in screen by touch.


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