1986 camaro has been sitting in garage for far too many years. Just bought a new battery and added some gas and it fired right up, almost.. the problem I have is the alternator light in dash has a slight glow at idle it goes away when I give it gas, I assumed the alt is not putting out enough voltage, but the voltage on the battery terminal when running at idle is 14.3 volts, when car is off the voltage reads 13 volts. isn't 14.3 volts enough at idle? It is probably the original alternator, The terminal to the battery seem tight and the battery is brand new, any suggestion? thanks for any help. Jon

 

Your charging voltage at idle seems sufficient. The ALT lamp can turn on for various reasons, but the causes can depend upon what engine you have. Is it carbed (L69/LG4) or TPI (LB9)?

 

Unfortunately it's the 2.8 v6 fuel injected. The car has been sitting for quite some time, the light did the same time before it sat, when the battery was bad, I would have to jump it to start it, I just assumed the alt couldn't charge the bad battery very well, so I put a new battery in started up fine but the light is still the same. it is never easy is it. Jon

 

There is a 100Ω resistance between the ignition switch main power and the voltage regulator in the alternator. This connection is paralleled by the ALT indicator lamp, which receives power from the GAGE fuse. Obviously, the fuse is intact or the lamp wouldn't operate at all. If the 100Ω connection is open for some reason, the lamp will illuminate since it would provide power to the regulator. If the lamp is the wrong type, it will also glow. Make sure the indicator lamp is a ML168. Remove the lamp and check for power at the regulator brown wire with the ignition on. There should be at least 8V present.