[169mph]

I took her for drive yesterday and she idled nice and smooth. I didn’t change anything. Started her today and the idle issue is back. I kept the engine from dying until engine was warmed up and then I revved the engine up three or four times. The engine idled fine until I turned the headlights. Immediately after turning the lights on the engine acted like it was going to die. The same thing happened when I turned electric fan on. Note that these issues usually go away after I’ve been driving her for 5-10 miles. Could this be alternator issue? Thanks, Mike