If you take this image:
Is it possible to make a gradient in Illustrator that follows that path?
I made something similar (just not with a single path, but with the pen tool) and I want to have the gradient follow the shape, but instead it just goes either linear (top to bottom) or radial (from the inside out). I want to have the start of the spiral lighter and than the tip in the center to be darker.
Look at the images – you choose the same options and get the result –
You select the path and invoke GRADIENT panel where you choose between 3 STROKE options according to the desired effect: