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Adding used vegetable oil to diesel in tank

Hi. My 19 year old son has a deep fat fryer and over a year has accumulated 2 gallons of used vegetable oil. I drive a 1998 Jetta TDI which I run on regular diesel and bio diesel, depending on where I fill up. My son wants to filter the vegetable oil and add it to my tank. He says he thinks adding one gallon to an almost full tank should be fine. Is he right? Should I let him try it or am I going to ruin my engine?

Can’t see where this is worth the risk. $6 of diesel vs. your car…

Agreed. Also, how is going to filter the stuff? He needs an actual WVO filtering set up-- running it through a sock or handkerchief won’t do.

It is not that simple. It needs to be processed before use. Well it does if you want that TDI to run right. It is certainly not worth the trouble for two gallons.

If you want to find out more specifics, check out the TDI club. http://www.tdiclub.com/ You may even to be able to hook up with someone local to you that processed the stuff.

He is a 19 year old. Let him test it on his car(right) first.Then you can congragulate him for being a maroon.