Throttle jump

I have a 2000 Oldsmobile Alero, sometimes the throttle will buck and oscillate. It does this throughout the throttle range but is most noticeable at idle and full throttle. Have cleaned the throttle body and it didn't help. Any ideas of what to check next? I've heard things about the tps, iac, and egr valve causing similar problems. (automatic transmission, 140,000 mi 3.4L V6 stock everything)

Welcome to AF.

Throttle jump? Can you clarify? Are you sure this is not a misfire condition? When was the last basic tuneup like spark plugs, ignition wires, fuel filter?