unless there is an electrician on here that knows different, you just about have to remove them to check them accurately. use volt meter or ground the plug and apply 12 volts manually, careful, it gets hot.
however, i didnt remove injector lines when doing mine.
You may find something doing a search, but using the multi-meter on the ohm setting, unplug the wire at the relay box, there will be five female ends, touch the red lead to #1 and the black lead to a ground, I use the bolt holding the relay to the inner fender. Do this for each plug.
You're looking for less than 1.
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