I've searched high and low, but nothing on warm and cold surging. This just started this morning. Idle surges from 1000 to 1800 RPM when cold. Surging slows a bit, but surges from 1200 to 2300 RPM when warm. No engine lights or codes detected. When placed in gear, you have to really ride the brake or she'll take off like a bat out of hell. Just started out of the blue. Drove perfectly yesterday.

If I've missed a thread that deals with this, please point me in the right direction.

 

vacuum leak needs finding

 

Idle Air Control Valve (IACV) may need cleaned.