hard starting

[kglowacky]

My LS1 2002 has a hard time 1st starting for the day. Turn key on, let fuel pump run then try to start. It will crank and crank start to spit and flutter then will start after 20 seconds then the rest of day it runs good until yesterday. went to store came out won't start. Crank crank flutter spit but won't start. Towed home. 5 hrs later crank crank sputter sputter then it started. Thinking fuel problem filter or pump. any sensors I need to consider
Thoughts

[LS short box]

Does the fuel pump cycle like it should when you turn the key to start?
Have you checked the fuel pressure. Oreilly's will "loan" you pressure tester that you can attach to the fuel rail. Should be about 58 psi when running.
LS swaps love/need good grounds. Main neg cable from the battery directly to the engine block.
The ECM 12 volt constant should be directly from the battery.

[kglowacky]

fuel pump I can hear cycling when key is turned on but I think I didn't hear it yesterday at first. and it did start up after cranking it a few times. Will check fuel pressure next.

[TrybalRage]

I would check not only the pressure but what the pressure is after sitting. If the system is "bleeding down" when not running then you've got really low pressure at start up.

[kglowacky]

Good point

[leegreen]

+1 for check fuel pressure

have you scanned for codes?

[biketopia]

Another suggestion for checking fuel pressure. How is your pressure regulated? Dedicated regulator, factory rail-mounted, C-5 style fuel filter?

[kglowacky]

C-5 style corvette filter

[AussieinNC]

Check fuel pump relay
Check main ground battery to engine and tow grounds at rear of block
Check fuel pressure leak down
Check crank sensor