I usually class all of these additives as "Snake Oil" and don't bother with them but I remember MDP posting about this stuff when he gave up his S/C and bought the Audi. I bought a bottle and then promptly sold the V6 and haven't put any into the V8 because I think the engine is still a bit new to need these things.
So what is the verdict - useful additive or Snake Oil? 2020 Pangea Green 1st Edition D240 New Defender 110 is here and loving it
2018 Melting Silver Mini Countryman PHEV - soon to be replaced
2015MY Corris Grey SDv6 HSE Dynamic, the best car I have ever owned, totally reliable only a cou0le of rattles in 3 years, now no longer in my care
Also in my garage is a 1996 TDi300 Defender 90 County HT made into a fake CSW