fuel injectors

today my truck wouldn't start so i had some friends come over to help. while cranking the engine there was no fuel coming out of the injectors. i first checked the fuse it was good. then we checked the fuel pump which is working fine. we then checked the voltage across the injectors it was 12 which i belive is correct. the truck was running fine this morning i then put a tach on and then it wouldn't start. the only connections made were to a 12v source off the fuse box, a ground, the dimmer switch and ont to the negitive on the coil. then we did the above and took out the tach so it would be just like it was before. still nothing. i then took out the throttle body and cleaned it out to see if anything was clogged it seemed to be fine and the pressure regulator was perfect. it's an 89 gmc 2500 with a 350 and a holley 670 cfm throttle body which was put on last year and never gave me any problems. any idea on what might cause this?

a bad ignition module. if it doesn't reference to the ecm, the injectors don't fire. try that

i did still doesn't give any gas

Pressure regulator inop?

how would i test the pressure regulator?

I'm not really sure. I know that you can make these adjustable to compensate for more airflow if running in a lean condition. A factory service manual may explain how to test it. Unfortunately, I don't have one. Sorry if my post was misleading.

it was the module just didn't let the fuel system build pressure
thanks for the help