Streetbeef, please dont take this the wrong way as im only trying to protect people rather than discredit anything you say, but that doesnt seem quite right.
I'm not sure if there have been any new developments with regards to this so I may be wrong but as far as I was aware there is only one setting with terraclean, so I would research this and ensure you don't get ripped off.
It is different for petrol and diesel but basically just cleans the fuel system and injectors and normally involves one can of chemicals into the fuel line to break everything down and the other to flush it all out via the return.
As such I don't know how there is more than one setting as the car just runs on the can of chemicals until its all gone then the second can flushes everything out. Once they've finished that's it. It normally takes between 50-90 min depending on the car and how easy it is to access the fuel lines in the first place.
I dont think there is any other way to do that if It makes sense.
Here is a pic of one of the machines and the cans, and also my tdi hooked up to the fuel lines.
Google Ed China terraclean if you are unsure of everything and im sure you'll see everything you need. There is an episode of wheeler dealers that he uses it on a jag which will explain it all. By the way I think there is one machine for diesel and a different for petrol.
My understanding is that Terraclean was originally designed as a replacement fuel and underwent years of testing and research. In the end it turned out to be too expensive so was not feasible. However during the testing they discovered that the engines it was used on were all being cleaned by the product so it was re engineered to be the cleaning solution it is now. As a result It is guaranteed to work, how much just depends on the state of the individuals car in the first place.
