need some help. driveability problem

[pontiac5oh]

i have a 99 chevy suburban 4X4 5.7l . it will not start cold. when i spray carb cleaner in the TB, it starts up and idles but is VERY sluggish to drive. i've got 50psi fuel pressure. i see spec on it is 60-66psi. will this 10psi differance allow me NOT to start when cold and to run very sluggishly/stall when i try to drive? plugs and wires are new along with cap. i have good strong spark. once the car gets hot it will sometimes start but it still runs sluggishly no matter what. when it cranks and doesn't start the ckp sensor is reading 150-250 rpms, so i know thats working properly. please, any help greatly appreciated!

no codes in pcm

[GoFastPadre]

I had the same trouble on my Sierra started and ran like crap till it warmed up, then out of the blue it cleared up and everythig was peachey. Then a shorttime later the fuel pump died., So I had a new one installed and after about two days it would start fine then at about 1500 rpm it would just cut out like it had no fiuel.I took it back to the shop (slowly) and had it checked out and my mecanic told me they were not supposed to start on less than 60 psi. I put in a new pump and everything was peachey again. Sorry soooooo long, but I hope it helps. Chris

[collinsperformance]

have you checked to see if there are any fault codes stored? you might have a few issues......mike