I went through this process on a petrol MINI Cooper S - made a huge difference. In that case, the exhaust gasses being recirculated caused the buildup. Earlier models were not direct injected (instead, injecting the fuel further up the intake) and so were able to 'self clean' somewhat.
Would be interested to hear the responses to this question, as my D4 had it's turbo drain fixed relatively late (104k km). Drives like a champ though, so if it does need doing, it isn't showing much sign of it!
2010 TDV6 3.0L Discovery 4 SE remapped to RRS output, Alaska White, GME XRS-330c, IIDTool BT, Dual Battery, Apple CarPlay, OEM Retrofitted: Cornering lights, Door card lights, Power + Heated Seats, Logic 7 audio
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