There is a light on your dash that tells you when you are low on oil (looks like an old fashioned oil can - the kind they used to use on locomotives until McCoy invented his oiler). This light gets its signal from the oil level sending unit that is indeed where you describe it. You do have to take off the oil pan to fix the leak. (don't forget to order a new oil pan gasket also)

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D