Cetane booster

DJ 190

A2OC Donor
I don't have any experience of this type of fuel additive. It's cost per litre seems to be VERY low .... 1.5 ppl ! It's not too expensive so you could try it out "for Research purposes" and report back to the A2OC! I add 2-stroke synthetic oil to my diesel because of the perceptible reduction in noise. Fuel is noted to be one of the most price-sensitive products on the market. Adding anything to that fuel obviously increases its price per litre, so it's got to be beneficial. Finally, from what I recall, "Which" seemed to indicate that it wasn't worth paying the higher cost of the premium fuels (same brand but a higher octane rating) in the hope of recovering it with higher mileages from that fill.

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Well-Known Member
I'd be tempted to use something like the Hydra fuel additive if running the car on 'home brewed' bio diesel or veg oil but would not bother otherwise.
The switch to ULSD fuels removed the natural lubricity properties of sulphur. The additive packages used by the oil companies should compensate for this but it can do no harm to add your own 2T oil for good measure. Apart from added lubrication of the pump and injector internals there is also lots of positive feedback and other benefits noted

If you plan to try it, pick a low ash 2T oil to the spec listed in the thread - https://www.a2oc.net/community/inde...l-in-diesel-anyone-tried-it.19041/post-144544

Cheers Spike


A2OC Donor
Another MIllers Oils user here too alongside Shell Optimax (remapped 75 TDI).

Depronman did a diesel purge on my A2 only to find the fuel was the cleanest he'd seen - I'd used this additive twice before this
over a few thousand miles.


I have experimented with Cetane additives and found no statistically significant improvement, certainly didn't obviously pay for itself.


Anyone used this? Not so much for the increased cetane number but for smoother running.

hydra fuel additives
I have used it for a few fills now.

A reduction in clatter seems quite obvious. The lowest smoke I've seen measured in my years of ownership, on the last MOT, was a surprise one that I'll keep an eye on to see if it repeats itself in December.

I've been using the cheapest Diesel available, which is generally a supermarket brand around 3p less than the Fuel companies forecourt price.
Given the Cetane enhancer is around 1.5p per litre, I'm still saving monies.
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Cetane additives are supposed to improve combustion in diesels similar to higher octane numbers in petrol.
Getting the right amount would perhaps be dependant on knowing the base level of the fuel you're using........not something to easy to do at home.....lol
If its cheap enough why not try some for a while and perhaps vary the amount over a few fill ups noting if you notice any difference....
I've just tried it - I bought the Archoil brand. I put in about 20ml and the tank had probably 25 litres in it, so that's 1:1250 isn't it.
The engine definitely seemed to run slightly more quietly and freely, and I could take the revs 100rpm lower in the higher gears before having to change down. It's always hard to be sure about it, but Barbara commented that it seemed smooth, and she isn't mechanically minded at all.
I'm currently on supermarket fuel as it was so cheap (121.9p/l)
Problem: the stuff doesn't just smell, it stinks. Worse than diesel. Next time I'm using throwaway gloves like the ones at fuel garages. And I won't be keeping the bottle in the car either; it's staying in the garage.
Will report again in a while.