OBD code p0121 for throttle petal sensor A electrical circuit out of range, changed petal an cleaned the throttle body as well. Now engine idling extremely high while in park an around 1300 rims when in gear.

What is your question?

Can hear and feel engine surging while driving at both highway and street speeds. Will sometime idle at normal range if after starting I shift from park into gear then back to park. This will change back to high rims as soon as I shift into gear and began to drive.

What makes this problem better or worse?

Nothing, stays the same all the time

How long has your 2009 Pontiac G6 had this problem?

Two weeks