This -may- be a stupid question if this is actually normal for these engines (Aurora Northstar) but I thought I'd ask anyway.
There'* a small mechanical valve or maybe a sensor near the firewall that enters the black part of the engine right above the steering fluid reservoir that'* making an awful lot of noise that sounds like arcing. If you pull the sensor out (there'* nothing but a gasket to hold it in) the piece of metal inside it flops around freely. I took it out with the engine off, of course, so I don't know what it actually does when it'* on but I'd imagine it just vibrates rapidly.
Seems to use a similar wire to the spark plugs but the wire leads into the top center edge of the engine, if you hold the wire you can feel a strong vibration coming from it.
I can't find the part anywhere on any diagrams or by a google search of the part number.
I'm not sure if the noise is normal though as I've heard it on a lot of GM cars and it'* only really noticeable if you open the hood, though I haven't heard it on any other brand of car so at the very least I'd like to know what it is and what it does so I can satisfy my curiosity
It says "2057" and "Made in USA" on the outer barrel and it'* a silver cylinder with an "F" stamped on the inside disc I think.