dousing with MOPAR CC cleaner would do its job perfectly here. Careful dripping with a pipe/funnel system would work - IDK how the ports are shaped or accessed but pretty sure this remedy could work.

I have seen a mitsubish GDI engine being decoked with it by leaving it overnight in the engine, that engine refuses to run if it gets carboned.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)