Hey,
I have a 1996 Blazer 4.3 and a week or so ago I started to notice a whirring or humming type noise coming from under the hood. The noise seems to match RPMs, but isn't very loud... it is most noticeable when sitting at a light or driving slow -- much faster and engine/road noise drown out the humming.
Now, I have noticed that the Voltmeter is running very low. It's normally right inthe middle of the gauge at about 14 (right ?), and now it's almost down in the red (but not quite).
I'm thinking that it's probably the alternator... what do you think?
If it matters, I haven't really noticed any performance change, and it does still start fine and will run the lights, radio, etc with no problem.
Thanks for the help.
Z