My personal experiment with my 2001 TDI is in progress. The details of my setup are basically like any good two tank hot WVO system -- heated tank, heated filter, aluminum hose in hose fuel line, veg therm for extra kick, 2 three port hydroforce valves, veg oil looped into heated filter. I pugre wvo back to wvo tank for about 10 - 20 seconds before switching do diesel to minimalize cross contamination. I am in TN where it does not get real cold. Startup fuel high blends of commercial biodiesel usually. I pan tested all but a couple tanks of oil i got from a friend that i put in it and it was all crackle free and filtered several hours through a 5 or 1 micron nominal filter bag as i was drying the oil. Then filtered again as i pumped into car.

I always said i would get an elsbett system if i ever greased out a TDI but then I was reading how elsbett recommends two tanks for wvo since it is more viscous and it can't hurt either so i said well i have to do the two tank system anyway so i might as well do that first. My system costs 700.00 all said and done and that is half of elsbett system. Plus, greasecar and frybrid was so successful and i figured people just must be getting along fine in their american wvo system tdi's so i thought, i'll give it a try and be part of the experiment. In the name of shadetree science (and fun) i greased out my TDI with a heated fuel system only. No real studies i have found document what happens when you run straight hot filtered WVO in a TDI without modifying the engine components. This is what american wvo systems are. They are not conversions. They are just putting hot oil in your engine.
Everything else aside, that is what i wanted to find out, does this work good or do you need to modify injectors and other things.


I wanted to pop test injectors before i started but i figured they could not be bad with only 63,000 miles so i did not bother getting the pop tester set up and resolved to test soon after. I changed my oil and switched over at 63,000. It runs real smooth great initially. If i never think about it all is great. If i think about it and listen, after a few thousand miles i think i hear a little extra injector nailing on wvo. I changed oil at 5,000 miles. Another 5,000 miles go on wvo. No problems but it seems a little louder on wvo still. No louder than before but i notice it if i look for it. If i dont look for it i dont notice anything. It could all be in my head. I changed oil again.

When i run out of WVO i drive on b99 for several days to work and back and i think i notice it is a little easier to start. Hmm, injectors clogging a little. So i play around a little more by driving 3-5 miles before shut down on (bio)diesel insted of 1 - 2. That seems to help. Seems to start normal most of time except when cold, cranking is slow. I wonder if it could be just battery or if it was slow to crank anyway before wvo. I did not have the car last winter.

Jan 26, 2008 So over the last moth the car has gotten slow to crank. Last week it was real slow crank. I put wifes jetta on it to jump. Still slow crank. It is not battery. THere are about 13,000 miles on wvo of last 18,000. I have not flipped the switch since. I have driven 250 miles on about B20 and the car seems to get easier to start. I am waiting for a real cold morning to say for sure. I told my wife and my friend to not flip the switch on theirs until we pop test the injectors and make sure they are good. They only have 1500 miles on WVO and can switch until i get the pop tester built but i would like to have some clean before and after tests.  We all have exact same system and have been using same wvo. 

I will pop test the injectors and compression test all car.   In my experience, i did everything that could be expected from a two tank wvo user, and i think the injectors just cannot take it and an elsbett system will have to be added. That is a good idea in any respect but it would be nice to know if it was necessary. So from here if compression and injectors check out on my car, experiment goes on and maybe i try diluting wvo with biodiesel.  In which case, i can happily say, i tried and i know you need injectors designed for WVO in a TDI and if compression is good and my engine is not damaged i will be very happy and I will make my car happy with an Elsbett system added.

That is my story. i'll keep you all posted. I would love to here from others who have been using wvo in TDI and see how they are doing.