That would be a part number. Serial numbers are different for every part. Use the web site for an auto parts store to look up the injector part number for your car and the car the replacement injector came from. If they list different numbers, you will not know why they are different, but they still could interchange. If they list the same numbers, logic would say they are the same, but you have to be careful that the number they list is actually for that specific injector. Some stores use that number just to get started, then they have to look further to narrow it down to the correct application.
You can also have the parts looked up at a salvage yard in the "Hollander Guide". Those list every part for a specific car model and year, with a code number. You look that number up in the back of the book and it will list every application that used that part.
Be aware that injectors can be different depending on whether the car has a manual or automatic transmission. Also, Ford includes letters in their part numbers to indicate the year that part was made. You can have the same parts, but if they were made in different years, part of the part numbers will be different.
Wednesday, January 18th, 2017 AT 3:38 PM