[Focus man. Focus.]

If I were you I wouldn't flush anything. Not unless you have been doing it regularly. Engine flushes have been proven to cause more problems than they are worth. They sometimes cause oil and carbon build up to break off and clog oil passage ways and drainage ports, which in turn could lead to engine failure. The same goes for a fuel system flush. These types of services are NOT recomended by vechicle manufactures.

Do a quick google search and you will find related documentation backing up my statment.