Droyalone, make sure the battery is in good shape - have it load tested - when you talk about the 'needles flying all over the place' it kind of reminds me of a battery with an 'open' or a very weak cable connection. I've seen the negative ground cable at the battery get weak or broken, as well. The negative battery post on my daughter's 98 Intrigue did exactly that, (it actually pulled right out of the battery). Check that before doing the more expensive stuff.