ok my car is not running its a 98 ls1 with 10# boost vortech and just installed a intank pump 255 lph. now the car will not run just spits and spudders. it will rev up ok in the drive way but will die out when i go to drive it just move it...and will not hold fuel pressure when car is shut off. when i turn the key on fuel pressure is at 20psi then start up 30 psi then rev up 31 psi thats getting in to boost any help?

 

Bad pump? fuel pressure on mine is 62psi at idle.