Blogging the A3 Jetta Conversion. We did this on a 98 and 99 A3 Jettas. Note: This system may not work good on this Direct Injection engine. After going 18,000 after an install and doing more reading trying to find success stories with a simple Hot WVO Fuel System in a TDI,  it may be that direct injection engines need new injectors for WVO. See here: http://journeytoforever.org/biodiesel_svo.html   Also , see my blog for running data of the system. I have the same system on my 2001 TDI. Nevertheless, this system is as good or better and several hundred cheaper any commercial heated fuel system such as greasecar and frybrid and I will give it its fair try on the TDIs. The worst that will happen is we will have to add Elsbett injectors and glow plugs. That would be one killer WVO system and if that does not work on a TDI than nothing will.