man, I wish I could offer you some garunteed advice on this topic... Well, in your book for your car, does it tell you what/if there is a sensor that this needle is drawing it's current from as it's main source? if so, you will need to check continuity throughout this switch, relay, not just the wiring that is in the dash.. But from my slight understanding of Electrical components I know that what you are describing sounds like possibly a relay which isn't working straight, but without a book, I can't give you a garunteed answer... So basically try and follow the wires if you can, or read the books schematics and find out where the main source is and work your way from the main source up..
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