2003 6Spd manual

I have a light buzz noise that comes and goes every few seconds. Cant figure out where its coming from but sounds like behind the intake manifold. Its not a steady buzz it starts and stops randomly every few seconds while idling and it almost sounds like an electric buzz sound. Its not that loud you only hear it with hood open and for some reason when the cooling fans turn on the buzz starts and continues until the fans turn off, then starts buzzing randomly again. Wtf is this? Car runs perfect by the way.