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Old 01-01-2008, 01:00 PM   #1
haysonj
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Tach problem

My tach jumps all over the place at idle when I turn on the heater or AC fan It smooths out as the RPM,s come up. I have it getting power directly from the the fuse box on a separate fuse. I was wondering if the Alt not charging at idle would have anything to do with this. Its a MSD 6A ignition and a stock Tach
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Old 01-01-2008, 01:50 PM   #2
WorkinLonghorn
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Re: Tach problem

Mine (stock set-up) did that jumping around when the connection to the coil needed cleaning and tightening,if that helps any.
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Old 01-01-2008, 04:27 PM   #3
tx71smallblock
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Re: Tach problem

a good check of all conections including the fuse would not hurt
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