Interesting David. Most new car manufacturers say not to use the bio fuels or the warranty is voided.
I notice McDonalds say they run their fleet on old cooking oil without problems. Locally, one young scaffolder runs an old Peugeot on cooking oil straight from the chip shop without processing it.
Myself, i ran a Peugeot for 12 years on nothing but gas oil. It actually went a bit faster than a normal pump diesel fuel.