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Discussion Starter #1
When I run the 289 engine with just the foglights on (and not headlight or parking lights), after a short while, they flicker off and on randomly. I believe they're wired correctly, as the dash and tail lights illuminate when the 'fogs' are turned on. Strangely, when I turn the parking lights on, the problem stops and the foglights appear to shine just a bit brighter. Does this have to do with the Alternator? Brand new voltage regulator? 15A (maybe it's 20, I forgot) circuit breaker? And why does my ALT light stay illuminated? Thanks to whoever has the time to reply.
 

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hows your ground wires on your foglights? if its a so-so connection i could see them doing that.
 

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Discussion Starter #3
Thanks for the quick reply. I did a ground-up resto and am pretty certain they're good solid connections. If not, how would one explain the problem going away when I turn the parking lights on? They'll even do it when I shut the engine off and the car is absolutely still. Demons perhaps?
 

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wow im not sure then..im not exactly familiar with the wiring schematics on a classic. Demons haha yeah my next guess
 

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More than likely its the circuit breaker. I think the '67 are wired like the '66 and the fog lights can be ON anytime the tail lights are on even if the breaker is disconnected. That would explain why they don't flicker when the parking or headlights are on. For a temporary check, wire directly across the breaker and see if the problem goes away. I am not sure why they thought they needed that breaker to begin with since the fog lights can be powered by the tail lights even if the breaker is bad. They only wanted to protect something PART of the time??

If not used for a long time those breakers are iffy. Mine was completely open circuit although I was able to pull it apart and clean the contacts and it again works. I have a picture of its innards posted here somewhere.

You ALT light is more difficult. Probably means you aren't charging the battery. Check the battery voltage with the car running. It should be 14-14.5 V.
 
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