2004 Pontiac Bonneville • FWD Automatic • 148,000 miles

I have a 94 Pontiac Bonneville with the northsater V8. This week its been idling fast, 1700 rpm sometimes 2500, most of the time it will idle down after serveral minutes. Sometimes I dont have to touch the accelerator and it will cruise 35mph. Another symptom is in the morning or after sitting for the day (cold starts) it wont idle, I have to feather the throttle for a minute to keep running. Winter temps here are around 15 degrees. I'm sure its a sensor but which one?
January 29, 2011.

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