ok, here's my problem: i have a b16a and i have a problem with it hesitating when i give it gas, usually going up hills/around turns/revving out slowly. i have replaced the air and fuel filters, installed a 255lph fuel pump, and an adjustable fuel pressure regulator. i was thinking it was the fuel pressure, but increasing it didn't help. i noticed when i installed the fuel pressure gauge that the pressure only increased about 2 psi when i revved the motor, and it wasn't really a solid 2 psi, it was more like the needle bouncing around. i thought that it should increase more than that, but i don't know. another thought was that the throttle position sensor wasn't adjusted properly, since i took it off when i swapped the engine. i really don't know what the problem is, so any help is appreciated. thanks.

 

as for the fuel, that sounds about right. It really only bounces up a few psi when i rev it.

what kind of exhaust are you running?

 

i have 2.25" with a 12" resonator and an hks hi-power muffler. i tried turning my fuel pressure up to about 40 psi and it magically began to rise about 4 psi when i hit the throttle like it should. i'm beginning to think i have a vaccum leak or a sticking fuel pressure regulator. sometimes it's fine and sometimes the hesitation is really annoying.