Help needed....Surging IDLE issues

Hello and thanks for viewing...

I have a 1989 Dodge Power Ram W100 4x4, 5.2L V8, auto trans...Currently, at COLD startup, it idles fine for a few minutes. Then, at warmup, the engine idle surges from normal idle down to near stalling.

Any advice??....Do you think it's the IDLE CONTROL VALVE/SENSOR or what??

Thanks for all help and advice!!

Mike