thanks for the input thats the best feedback I've got on here everyone keeps saying about checking them with the scanner . So do they have to be removed to test them? if they're bad can they be rebuilt or dose the injector need replaced
You can test them in the truck. You just have to get some adapters to hook into the fuel return port. Kent Moore tool J-45873-30 is the kit of 4 adapters that you need. Once you have those you'll need some barb adapter fittings to thread into the side of those, some hose, and some graduated cylinders, or you can buy Kent Moore tool J-45873 which has all the hoses, fittings, and graduated cylinders (just to be clear, this kit does not include the adapters in J-45873-30).
If you want to do it the really cheap way, you can use one of the 90 degree return fittings from one of your injectors and test them one at a time, doing it this way can make a big mess though.
They should not return more than 5 mL during a 15 second crank cycle.