Ammeter issue

[Torchred73]

Hey guys, its been a loooong time since i posted here last, but have enjoyed reading many of the posts on a regular basis.
I am having an issue with the Ammeter Gauge on the 73. Up untill now it has worked as it should and driving this morning it was still good. I let the car sit, parked in the garage over lunch and then decided to go out again. When I turned the key to the accessory position, the gauges came to life in their usual manner, including the ammeter. However, when I started the car, the ammeter gauge flipped all the way to the +40 and after 4-5 seconds began to fill with smoke!! I immediately shut her down and disconnected the battery. Did a cursory check and found no shorts or fried wires so decided to try again. Same thing, good in "ACC" but smokes in "RUN".
So my question is: Did some gremlin creep into my car during a lunch break or is this indicitive of a gauge heading south?

[slofut]

Originally Posted by Torchred73

Hey guys, its been a loooong time since i posted here last, but have enjoyed reading many of the posts on a regular basis.
I am having an issue with the Ammeter Gauge on the 73. Up untill now it has worked as it should and driving this morning it was still good. I let the car sit, parked in the garage over lunch and then decided to go out again. When I turned the key to the accessory position, the gauges came to life in their usual manner, including the ammeter. However, when I started the car, the ammeter gauge flipped all the way to the +40 and after 4-5 seconds began to fill with smoke!! I immediately shut her down and disconnected the battery. Did a cursory check and found no shorts or fried wires so decided to try again. Same thing, good in "ACC" but smokes in "RUN".
So my question is: Did some gremlin creep into my car during a lunch break or is this indicitive of a gauge heading south?

Maybe the starter or start circuit is seeking ground thru the ammeter. Have you done anything under the hood lately? Or in the dash? Others more familiar should chime in soon.

[Richard454]

I'm thinking the shunt in the Ammeter is flowing all the current...check the conditions of the connections at the horn relay.

The shunt is basically there to turn away or rather make the current- follow a different path. Sounds like the path is now open and causing all the power to go through the Ammeter...

One of the many reasons I'm having my ammeter converted to a voltmeter...which GM changed to in 77...

Richard