Circuit/System Verification
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
Ignition ON, use a scan tool to observe the throttle position (TP) sensor 1 indicated position. Throttle position should increase as pedal is applied and decrease as pedal is released. When no accelerator pedal activity is detected, the throttle position will return to the spring loaded default position.