i have problem my car will start up, some time's after i try starting it for 10 or more seconds it will sometimes start and run for a about 20 seconds and cut off i have replaced the fuel pump and have checked fuel pressure with a guage pressure was good... i have used a noid light to check injector pulse and it would not pulse when the car would not run but after 10-20 seconds when the car would act like it's gunna start it would start pulsing and would run for about 30 sec... i have checked the spark and the plugs are getting fire. what other check can i run .. i have also hooked up a diagnostic tool and only got a code 12 which i was informed that was saying the ecm was working but not fault codes.. any thought or help would be greatly appreciate .. i can run any test or ohm out any wires just let me know ..i was thinking maby the injector drivers in the ecm may be going .

 

Test for a distributor reference signal to the ECM when it's not firing the injectors.

 

how would i go about that? what to i need to test and how..thank you