Hi. Ive got a 2004 2500hd with a 6.0l ls vortec motor. that ran well until it sat about a week and a half because i wasnt using it. And now it won't start. there is fuel pumping up at the injector rails. But No power at all at the injectors. It don't spit sputter do anything. unless you pour fuel in the throttle body. Then it starts up and runs till it burns all the fuel i poured in the throttle body and dies. Tested all the fuses and relay's associated with the pcm. Ecm and fuel system. And they test good. I also plugged a obd 2 scan tool in and there are no powertrain codes or dtc's. Im kinda stumped. What could this be. Crank sensor bad ?. Fryed Computer ?. Thanks

 

theft light on? theft codes are body codes so will not show up on a cheap code reader.
does your scan tool data show rpm when cranking

 

Back when i got this pickup. it had the ignition switch in the column Knocked out as the guy who had it lost the keys in a house fire. I did the passlock bypass and it has started fine ever since but the theft light has been on all the time and still is. Yeah the code reader I used I think shows live data but only reads abs and check engine codes. I'll see what the cranking rpms are. From what I've read there should be switched 12 volts at one of the 2 wires at each of the injectors and injector pulse on the other wire while cranking. I know there is no switched power at the injectors. I'll test if there is injector pulse there If I'm right about this ?. Thanks

 

the injectors are provided battery power at all times with the key in run....the pcm grds the injector to turn it on. The proper way to test it is with a noid light of the correct resistance ...the noid light should flash when cranking.

if you have a mechanics stethoscope....you can hear the injector click.

have you checked the injector 1 and injector 2 fuses in the underhood fuse box. these fuses direct feed from the ignition 1 relay