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Discussion Starter #1
ok first the stats 66 Coupe 6 cyl auto
replaced the engine gauge feed when I started the car all ran well but the ammeter now moves to the Charge side during acceleration. As a matter of fact the gauge moves all the way to the "c" during acceleration. The gauge moves back to the center at idle. Do I have a problem? If so any Ideas. Thanks guys
 

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Sorry to piggyback your post Lorwood but I had a question on mine mabe someone could answer both of ours at the same time. Mine constantly stays right in the middle where it should be even when starting car and does not appear to move. Is there a way to tell if it is functioning or not ? The previous owner removed original generator/regulator and put in a gm alternator if that matters.
 

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As a matter of fact the gauge moves all the way to the "c" during acceleration. The gauge moves back to the center at idle.
Are you saying it literally "touches" the C? or it just moves off the centerline?

What alternator are you running? Stock?

If so, here's the deal....it's normal for the gauge to move towards the "C" when the engine revs up (not just accelerating, but maintaining high RPMs). However, if everything is working properly, on a '66, this movement is barely noticable. Now, if your battery was low on charge (either from being "bad" or from leaving the headlights on, running a serious sound system, foglights/highbeams on, all of the above), then you might get a bit more movement, like maybe half way to the C.

Here's the bad part: the ammeter works by "siphoning" a bit of the current that is going to the battery. So, if your gauge is going all the way to "C", then either, you have too much current going through the gauge (a very bad thing) or you have A LOT of juice going to the battery....a lot of juice going to the battery can be caused by any/all of the things I listed before.

I assume the car is starting OK, and not cranking too slowly and will start if it sits for a few days. If that's all true, your battery is most likely OK. In which case, you have too much current going to the gauge. The most likely cause is simply a dirty connection between the "hot" post on the alternator, and the solenoid. Try cleaning up all your contacts, and see if that helps.

To the other poster with the GM single wire alternator: it depends on how he wired it up. Most likely, he bypassed all the wiring, and ran his own wire to the battery/solenoid. If that's the case, and that "new" wire is not tapped into, then your ammeter is not hooked up. But, you're not missing much.
 

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Discussion Starter #4
thanks for the answers all the wiring in the engine compartment is new all the connections are clean the regulator is new and a correct autolight regulator. The ammeter did not move until the new wiring harness was installed now the gauge moves all the way to the C when accelerating. so connections are good regulator is new so what could be the problem? thanks Ed
 

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I chased a similar problem on Midlife for 2-3 years without success. My ammeter, at times, would show heavy discharge or charge. I could get it to go back to normal by tugging on some wires on the left side of the underdash...sometimes. I've traced wiring schematics, and thought it might be at the VR junction plug not seating well. I too had all new harnesses under the hood, but not under the dash. I never did find the problem before I tore Midlife down to a rolling shell. I wish I could help you out...
 
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