Help Plz, strange idle and coolant smell

[nickpic83]

in my 94 i get an intermittent strange idle. mostly when is warm the idle will move around a bit 800-1000rpm. then if i stop and shut the car off like at a store then come back out and start it, it will idle very low like 500rpm them go up and down almost dying. with all this no matter what it drives fine then the idle eventually smooths out to normal. this only happens sometimes and there is no difference in weather or anything. the plugs(NGK) and wires(NGK) already have been done and also a synthetic oil change. it did this before and after this work

any ideas on what it could be??

also i get a slight coolant smell inside and outside. its very slight. i checked my coolant level many times and it does not seem to change at all. it doesnt seem to be leaking. no coolant on ground under car or anything like that, that i can tell. not sure if there is any common issues or not. my radiator isnt brown yet but it is an olive green but like i said i dont see a leak anywhere.

any thoughts?

thanks in advance...

[sdemo45]

I'm thinking these are separate issues. Coolant is likely your heater core hoses. Check your footwells for any puddles or discoloration. Rough idle could be alternator, battery... something electrical.

[nickpic83]

forgot to mention i put a new battery in it last month and its def good. also the alt is putting out over 14v but yeah i guess if it has enough load on it i could have an intermittent problem if its on its way out