"Standard run of the mill everyday Diesel"
12,000,000+ Commercial diesel vehicles with engines far newer and far more advanced than any JTD and run happily on the standard stuff without the need to decoke anything for hundreds of thousands of miles
They change the fuel filter every six weeks (6,000 miles) i.e. Regular fuel filter changes and longer journeys where the carbon soot doesn't have a chance to build up... They don't pop to the shop 2 mile down the road persay
... Short journey's? Buy a petrol car, they are more economical on this type of usage.
Two stroke oil (about 200ml to every full tank) helps keep things smooth and running happily too.
You can alleviate the issues by draining the water every couple of weeks from the bottom drain of the fuel filter housing, which also contains a lot of unburnt and settled, so called "cleaning detergents" too (working for VOSA we used to analyze them allong with the fuel as it was the easiest way to ascertain the use of illegal red diesel via the filter drain)
Leave the special "miracle fuels"
to the people who own super cars and who can actually afford wasting money on the stuff... A JTD isn't a super car after all, it's a common, all garden diesel
You have to understand that a standard diesel engine burns fuel by compression and the heat it produces from it causing combustion... Detergents added to fuel do work,for a short time, but.... They also cool down the combustion thus all the fuel isn't burnt off at the same temperature it would have been, so soot particles stick to the unburnt fuel and end up building a sooty gunge over time in the manifold... You also have to understand that using detergent laden fuels forces the ECU to adjust it's settings over time, they run leaner than they would, thus initially less carbon... Until a series of short journey's ruin that point.
Then when you have no choice but to fill up with standard fuel, the car doesn't like it and runs worse....
Nothing wrong with the standard stuff, just your ECU now having a dicky fit trying to re-adjust to the difference, it's richer.... But then again.... The average intelligence of a car owner will automatically think that it the last fuel they used is to blame and as a result , they go back to specialist fuel yet again... Just simply compounding the issue and putting yet more money into a fuel company's and the Governments pocket...
Not what you wanted to hear, but speaking from plenty of experience in the field
I'm sure some advocates of the stuff will differ and say "my car runs great on V-power, blah, blah"...
Good for them.... I just happen to see what this miracle stuff does on a technical level not just on a placebo level....
But, then again... Human's hate to admit that they waste money don't want to look stupid for doing so, so they will defend anything as a result