I have a 1997 Chevy K1500 ext cab short bed Z71 with a 5.7L 350 Vortec I snapped a rod so I bought a new short block from a 1999 C1500 Suburban I got the it rebuilt and in my truck I replaced everything on the motor but now it wont run it will start and stay running as long as you hold the key in the start postion. I have replaced the Timing Chain, Crank Sensor, Ignition Coil, Distributor, Spark Plugs, Spark Plug Wires. I check all the fuses and they are all good.