E31 = throttle control fault
When you have a problem in your throttle body motor circuit it will code this code.
I would check the wiring to the throttle body and make sure there are no broken wires.
Worse case is it is internal and the throttle body will have to be replaced.
After you repair/replace you will have to relearn the TB.
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.