Anybody ever use one of these? I noticed that AB sells one “Bosch fuel injector diagnostic test light” . I have a recurring misfire I’m trying to track down and I want to rule out the fuel injection. I can’t figure out how to use it though since it’s normally hooked to the injector plug with the engine running but you have to pull the intake off and unplug a bunch of stuff to get to the injector on these trucks. Only thing I can think of is to disable the ignition so it won’t start and then give it a few cranks with the intake manifold pulled off. I assume that would still send the proper signal to the injector?

 

Maybe pull the plug wires and the fuel pump relay.....you dont want to dump fuel into the cylinders for sure. Ild release the rail pressure as well.

 

Oh yeah good idea, seems like it should still work even with the fuel pump disabled