wow your '81 is a lot prettier than mine! What's that red thing in the garage????
Does the alternator light come on when you start the car or when the volts read 0? The charging circuit for the alternator runs through that light bulb..so if it is burned out the alternator never charges.
Also like danglerb said the instrument cluster is frought with contact issues..could be faulty contacts, grounds, etc etc..especially if you are seeing problems with other gauges.
On my '81, the oil pressure gauge was always pegged, the speedometer would not go above 30mph, the voltmeter jumped up and down constantly, and the temp gauge was dead...(other than that the cluster was fine
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Once i redid the contacts, everything worked (and i figured out i had a bad alternator)
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1990 C2 Cabriolet Guards Red
'81 928 Zinnmetallic Project Car (sold)
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'87 944na Maraschino Red Metallic (sold)
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