Have been having problems with cel code 420. In past this has been associated with gas cap. went by dealer the other day so stopped in and check on availability of seal associated with gas cap. Not available but new cap was $30. Didn't have to think twice about not paying that for gas cap. Was in to local auto parts yesterday and got talking about cel and association with refilling /gas cap. They had a replacement cap, made in USA, cost $7 or $11 with lock.
Don't see how dealer price encourages customers to shop at dealer.
Mickey