Does anyone have any experience of having terraclean performed on their car ?

My subaru has been pinking main dealer cant find any issues. Some people on a subaru forum suggested it could be carbon buildup and a terraclean treatment might help especially as car spends most of time in london traffic. Its done 108000 miles.

Terraclean website locator only gives a garage in Se London and im in Surrey / Sw London does anyone know of an operator more Sw of Lodon or a mobile operator ?

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