Of the suspect injector. If I remember correctly it should read between 11 and 14 ohms. Another way to check the injector is to start the engine and while it is running remove the suspect injector connector and listen for a rpm change. If the rpm doesn't change it confirms it is your injector. Hope this helps. I am sure there are many articles on this forum that can give you better troubleshooting guidance. My understanding is that the old style injectors are notorious for failing. i joined the ranks and upgraded to the new style injectors. I imagine that when one injector fails the others are soon to follow.