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.

Now on with the kit. This components are the same for any vehicle for a simple Hot WVO System - one without any modifications to the engine but just adds a heated fuel system as described. The components we got from the internet and local supply stores. For starters we have a heated 12 gallon fuel tank, Tempo TP12SC fuel tank. That goes to the Hose In Hose (HIH) going to to a heated fuel filter. From there the fuel line goes to a Standard 20 am Electric Vegtherm heater and then to the Fuel Selector Valve (FSV) and finally to the Inject ion Pump (IP). The return fuel from the injection pump (more fuel is pumped from the tank than is used by the engine so fuel is returned back to the tank by default) goes to a second FSV. Normally , depending on the switch configuration , fuel is returned to the diesel tank or returned into the supply circuit of WVO right before the filter. This returning of the WVO into the WVO supply line instead is called "looping" the fuel return.

That is a summary of the system. Details of each part follow. Here is a picture of under the hood when it is done. I abandoned the engine cover because i never liked it anyway. I like to see problems under my hood, not have them covered up.