06-02-2013, 07:12 AM
13.5v is normal. Not being an electrical kinda guy, I would wait for others to chime in on this one 
Are the tach digital? I'm guessing they are not. First off, tachs are terribly unreliable unless digital IMO. I would consider replacing them with Aetna Digital Tachs. LOVE these tachs!
Are both tachs getting erratic? If just one swap them and see if the issue follows the tach. If it does then you know it's a gauge problem, if it doesn't then you need look down stream.

Are the tach digital? I'm guessing they are not. First off, tachs are terribly unreliable unless digital IMO. I would consider replacing them with Aetna Digital Tachs. LOVE these tachs!
Are both tachs getting erratic? If just one swap them and see if the issue follows the tach. If it does then you know it's a gauge problem, if it doesn't then you need look down stream.


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