 not like a doctor sensitive you know you want it sensitive but not you want a mechanics one which is made for these things right if you use a block of wood you can hear it clicking but you can't hear that it's good it goes to thud like a dirty injector because it's a piece of wood or a plastic screwdriver do the same thing so just make sure you don't touch an ignition coil when you're listening to the injector bad i've gotten shocked a couple times it's been a little damp and i've