sv2105

At 45k miles, service stabilitrak warning followed by flashing check engine light and reduced engine power notification. This was caused by a bad throttle body. Replaced it, everything was fine. Fast forward to 91k miles. Service stabilitrak comes on again accompanied by flashing check engine light. Rough idle and hard shifting. Sounds like it's trying to stall out while idling. Changed spark plugs, coil packs, accelerator pedal sensor, battery and mass air flow sensor. Nothing has remedied the problem. First vehicle to ever stump me. Code is still coming up for the pedal sensor. Any ideas?