intial startup trouble

i am new to the forum and i have a 97 silverado 5.3 liter auto.

this truck will not start on its own. i've replaced the plugs and wires, cap and rotor, fuel filter and pump. all it does is crank over like its not getting any fuel. i can start it w/ a shot of ether and then it runs strong all day, and then starts up after it has run for a while, not easily though. if anybody has any suggestions i would greatly appreciate any help i can get.

i posted this under general tech   thanks

Somethings up with the injectors/throttle body.  my 99 was taking an extra turn of the key or two and i took it in to chevy when it was still on warranty.  they replaced something...can't recall what it was though then proceded to tell me they wanted a couple hundred to clean injectors which would require removing the throttle body.  i put a bottle or two of the fuel injector cleaner (big tank size) though and it's been running great since.