Low Fuel Pressure...?

I have a 92 RT Turbo with low fuel pressure or something. I am bpu with 450 injectors. I have decent compression (150) in all but in the #5 cylinder (135). My neo is currently set to +20 in the high throttle and +5 in the low throttle. My wideband jumps around alot which is why I put the car so rich. My gas mileage is around 150 miles to the tank. I have changed the the fuel filter, upgraded the fuel pump to a walbro, changed out the fuel pressure regulator, tps, isc, ecu, and a couple other things. The car randomly decides to hesitate and stutter whenever it wants. If I turn down the fuel, my wideband reads WAY too lean. Even at idle, my car reads dead lean. My #1 injector randomly cuts itself off and turns back on. I have had a few places try and solve it and nothing. The weird thing is that my car runs alittle bit smoother when my tank is completely full. The lower the fuel levels get the worse the car runs. Any ideas?

150 is perfect compression for a TT.

The NEO have issues that need to be fixed.

http://www.supercar-engineering.com/rubberducky/3S/Mods/TT/AFCNeo/index.html

More info can be found here
http://www.3si.org/forum/f1/apex-afc-neo-confirmed-programming-bug-karman-function-doesnt-work-419786

:iagree:

I would also check the O-ring for the fuel pump. I had a problem when I installed a Supra pump. It ran very well for a while than it went super lean. I checked everything I could think of before pulling the fuel pump. What happened was, when installing the pump, I didn't lube the O-ring and it folded over. Since it sealed fine at first, it was running properly. I guess the pressure eventually pushed the O-ring enough to cause a lean condition. Another symptom, I had was a longer than normal crank time before starting when the engine is allowed to sit for a while. Does you car start easily?

hmm.. interesting.. I need to crank my car too..
I do have an upgraded walbro installed, I'll have to check it out when I get a chance. I was thinking about checking the fuel pump as I was running out of options of what it MIGHT be. Thanks for your input. Hopefully have time to check it out this weekend.

edit: Was thinking.. I think the problem happened before the fuel pump install..

Check your ECU as well. Caps are probably leaking.