5.3_72gmc

I've got a 72 c10 with an ls1. Been fine. Put over 1000 miles on it already. But I parked it last night in the garage. Went out today and it wouldnt start. Just crank. Fuel pump isn't pumping and I'm not getting spark. Relay is good. Pump works fine If I jump the relay but it still won't start. Cam or crank sensor? I don't know. I would trace it all down but I've been very busy with other vehicles.

ls1nova71

iTrader: (4)

Fuses all good? Also check your grounds, if the pump isn't priming when you first turn the key, it isnt a crank or cam sensor. Likley isnt going to fix itself, so you're going to have to make time to check it out if you want it fixed. Just saying. ..

5.3_72gmc

All fuses are good. Checked continuity for the ground on the relay that comes from the ecu. Good grounds. Pump is grounded. Ecu is grounded. Have 12v to the relay as well. All fuses are good. Only have 8 fuses and 2 relays in total.

1964SS

iTrader: (1)

Check your constant and ignition wires to ecu. Orange and pinks to verify they are powered up. Do you have an obdII reader? Can you communicate with ecu at all?