I TOOK MY CAR AND HAD THE CODES CHECKED AT MY LOCAL BMW DEALER AND THE CODES CHECKED OUT TO BE MY SECONDARY AIR PUMP, SO I CHANGED THE PUMP WITH A USED ONE THAT I PURCHASED FROM A FRIEND, BUT MY CHECK ENGINE LIGHT IS STILL ON, WHAT MIGHT HAVE I DID WRONG OR WHAT ELSE DO I HAVE TO DO?
PLEASE HELP IF ANYONE KNOWS......