but i have an 84z28 (this isn't the dumb part) but since its gotten colder and kinda rainy here, it idle's like **** and the volts drop to below 13 (way below) just sitting at stop signs and lights my question is where should it idle it does around 1000 or so according to my broken *** tachometer (reads 6-6500 rpm on the interstate) and if i give it even half a turn up it runs way high and wants to buck when i try and stop like it doesn't want to stop (sigh) gotta love driving an old car everyday.
thanks in advance for any help guys

 

Vacuum leak?
Normally a car will idle itself up with a vacuum leak though.

 

idk been all over the engine and the hvac controls behind the dash (did the hiss fix) nothing i know of i suspect its the alternator i think someone replaced it with a lower amp one at some point was gonna get a lifetime warrantied one at work just to see but idk