hard to start cold

when i go to start in the morning i have to crank it over many times before it will start. i changed the plugs, the fuel filter, i can hear the fuel pump run. if i put a shot of wd40 or starting fluid in the air intake it will start right up, also if i plug it in at night it will also start up after a couple of tries, i was told it could be a feul pressure reg, or a coolent temp sensor. can anybody help. thanks for your time

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when i go to start in the morning i have to crank it over many times before it will start. i changed the plugs, the fuel filter, i can hear the fuel pump run. if i put a shot of wd40 or starting fluid in the air intake it will start right up, also if i plug it in at night it will also start up after a couple of tries, i was told it could be a feul pressure reg, or a coolent temp sensor. can anybody help. thanks for your time
sorry about that it is a 96 ck 1500 with a 305 vortec engine thank you