driver to ear trick. If you've confirmed that it is in fact not firing, then yes you can have the injector ohm in spec and have 12V at the injector and it still not fire. Was the car sitting for a while? With ethanol in fuels these days, they can gum up pretty fast. Quick check is use a 9 volt battery, wire it up and quicly touch the leads to the injector to fire the injector, do this multiple times. DO NOT LEAVE THE 9V BATTERY CONNECTED FOR MORE THAN A SECOND OR TWO, IF YOU DO THAN YOU CAN FRY THE INJECTOR. If it does start clicking, plug it back in and see if that takes care of the problem. If not then you need to troubleshoot further.