Had my car TerraClean'd

[Rolebama]

The last garage I worked at, the owner was an ex-BMW mechanic and he had a similar machine for petrols. I have to say that at first I was very sceptical, but after it had been used on a couple of older 3 series, I was decidedly impressed.
FWIW, I was running a 50/50 mix veg oil on the 306, and the emissions were super clean at MOT time. Castor oil gave a very noticeable increase in performance and mpg.