Crank no start, has fuel pressure.

[Dante2795]

Completely stumped here. Lb7 broke a crank, we swapped in a complete running engine back in it. Truck builds higher rail pressure than desired. It’s reading 9k psi cranking. But will not start. I am getting P0374 as well. Swapped in brand new cam and crank sensors and nothing. All wires appear fine. All grounds are good. Any ideas?

 

[Dante2795]

Also checked reluctor and that appears fine and not loose

 

[Chevy1925]

are the injectors firing? did you miss a ground on the block?

 

[Dante2795]

are the injectors firing? did you miss a ground on the block?

Injectors aren’t firing. I’ve checked the block grounds multiple times and they are good

 

[Dante2795]

Now it’s throwing p1500 and actual rail pressure is jumping 12k cranking. Rpm ranges from 90-200rpms

 

[ZeroGravity58]

I'd check all the wiring, the ficm won't fire the injectors without a proper cam signal

PO374 Code means the engine control module (ECM) replicates the signal received from the crankshaft position (CKP) sensor. This signal is sent to the fuel injection control module (FICM) through the engine speed signal circuit. The FICM uses this replicated signal to generate injection current and control the recharge of the fuel injection high voltage circuits. When cranking, the FICM has full control of the fuel injectors. The only input the FICM uses at this time is the engine speed signal from the ECM. The FICM monitors the signal along with the injection request signals from the ECM after the engine is running. If there is a problem with this signal, a DTC could set.

 

[Ron Nielson]

Check your codes here - likely a wiring issue https://www.dtcdecode.com/Chevrolet/P1500

 

[Dante2795]

Update. New ecm fixed it