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Old 08-29-2021, 06:12 AM
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Cobra Make, Engine: ERA #732, 428FE (447 CID), TKO600, Solid Flat Tappet Cam, Tons of Aluminum
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Quote:
Originally Posted by spf645 View Post
Do you think maybe the gauge could be part of the problem? Being that headlight surge and gauge needle bounce seem to happen at the same time. Just discovered that today.
An ammeter needle bounce, wiggle or "waver," as we like to say, is caused by one of two things: 1) An ammeter that just plain wavers, even when system current flow is rock solid (rare); or 2) Fluctuations in system current (more likely). Fluctuations in system current will be caused by one of two things: 1). Fluctuating load; or 2) Fluctuating generation. A really quick, simple test to see if your ammeter always wavers is to leave the engine off, but turn the lights on. The ammeter needle will of course move to the left showing a discharge and should be rock solid. If for some reason the needle wavers even with the engine off then that would be unusual. A fluctuating load, in a simple car like a Cobra, is unlikely, but possible. The most common reason for a wavering ammeter needle (when you never had one before) is you have fluctuating current because the alternator and voltage regulator, which work together, are misbehaving. An idle that is not holding steady can also cause the needle to waver but that will go away as you increase the revs.
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