Strange Idle
 

My car (80SC) starts right away when cold. However, it idles at around 600 to 700 rpm and the alternator light stays on until I give the gas pedal a bump. The light goes off but the idle is still low. Recently, after the car is warmed up and I've driven for for a while, (say for 20 to 30 minutes) when I stop the idle goes up to 1400-1600 rpm.

Does or can the idle have to be reset? What can I check? Thanks.

I had a similar problem. Low idle at startup, rich. And then it would clear up and idle would increase. I changed the relay under the passenger seat that controls the frequency valve. You should be able to hear the freq valve buzzing while engine is running. Try unplugging the relay with the engine running. If the idle changes the relay is probably ok. If no difference when you unplug the relay, it may be bad.

I will check this out tomorrow. Thanks