Hi - I've got a 1990 GMC 5.7L 4x2 pickup. When I turn it on, the temp
gauge goes all the way to the left and stays there (and when I turn it
off, it goes all the way to the right). Also, when I put my turn
signals on, the voltmeter moves left to right to left to right with
the ticking of the lights. I'm guessing this is a crazy electrical
thing, but where exactly under the hood should I be looking?