Idle Control Valve
 

I have read other threads and may think that my 86 Jetta GL, 1.8 gas may need a Idle Control Valve. Overall, it runs good but at 1000rpm at idle most of the time. At times it surges from 1200-almost stalling over and over. Next time I start it, it may be gone again. I have yet to hook up my cd deck but the cassette deck already installed switches on and off when the car idles like that. My guess is that there is not enough power to run it when it almost stalls. When looking for this part online, the cheapest one I found was $171 plus shipping. Does anyone know if that is the part I need or if there is a DIY fix for it? I am not sure where it is yet or how to remove it. It is -30c here with windchill so I have to be sure before freezing my a** off. Thank you