Fuel additives

[MartinJG]

I have always used Millers fuel additive on my diesels based on an A/B test between two vehicles (Peugeot 405 1.9) that was carried out by an independent source @ 1993 when I got my first diesel.  Putting aside the manufacturer's claims of improved economy and cleaner burn, it seems the net tangible and quantifiable result was improved performance of engine oil and extended life of the injectors. Of course, the usual conundrum must be whether the extra cost is worth it in the long run. I took the view that it was relevant to diesels. Never failed a smoke test, had relatively clean exhaust under load and my MOT tester reckoned they were among the cleanest TDI diesels he had tested. Given the differing characteristics of petrol combustion, is it worth using an additive and if so, which ones are folk using? The main reason I ask is it seems the good ones certainly reduce deposits in the cyclinders and presumably exgausting too which must surely improve performance and therefore minimise issues with the dreaded EGR.

[Jocko]

Only one I have used recently is Redex Fuel System Cleaner, and I found Asda the cheapest place to buy it.

[MartinJG]

Jocko

Redex seems to have been around for years. Did you notice any difference when you used it?

I should add that in my experience, I noticed a marginal increase in MPG of @2-3%.

[culzean]

Only one I have used recently is Redex Fuel System Cleaner, and I found Asda the cheapest place to buy it.

If people are buying expensive petrol just to get cleaners rather than higher octane they may as well just put some redex in the tank once a month or so.  Redex (and STP etc) are the best cleaners I have come across (see Redex melt the gunge and lacquer out of a motorbike carburettor ).   When petrol stands in the fuel system or evaporates it leaves a gum behind they when it is left turns into a harder lacquer,  the holes in injector nozzles are very fine and it they do get gummed up it destroys the spray pattern and affects fueling).

[MartinJG]

Only one I have used recently is Redex Fuel System Cleaner, and I found Asda the cheapest place to buy it.

If people are buying expensive petrol just to get cleaners rather than higher octane they may as well just put some redex in the tank once a month or so.  Redex (and STP etc) are the best cleaners I have come across (see Redex melt the gunge and lacquer out of a motorbike carburettor ).   When petrol stands in the fuel system or evaporates it leaves a gum behind they when it is left turns into a harder lacquer,  the holes in injector nozzles are very fine and it they do get gummed up it destroys the spray pattern and affects fueling).

Culzean

Spray pattern and therefore more efficient burn was one of the points raised in the report. They actually took 2 vehicles from new and then ran one with Millers and one without. After 200,000 miles, they checked all the key bits including the injector spray pattern which was noticeably better on the Millers vehicle. However, based on what you say, it makes more sense to add the stuff from time to time rather than every tank top up.

[Jocko]

Jocko

Redex seems to have been around for years. Did you notice any difference when you used it?

I should add that in my experience, I noticed a marginal increase in MPG of @2-3%.

Didn't make any difference that I was aware of but I'll add some again this year. At £3 for a bottle (two fill ups) it is hardly  a great expense. And I don't imaging it has any detrimental effect.

[olduser1]

Redex seems to work when customers use it prior to MOT + Italien Tune up run along the M way