Power to Injectors

Can leaking injectors causing the car to smoke and also do over-float when starting? I replaced these injectors but the car starts and stops in two to to five seconds without smoke. I test the battery power to the injectors and it is okay. But I tested the power from the ECM to the injector when the leaking injectors are on the engine, and I found no power at all. I see the ECM is okay, but there is no negative power after the car starts. I suspect the problem to be coming from the crankshaft/camshaft position sensor. Where can I locate it?