3vze fuel pressure issue

[GilbertG]

I’ve been pretty stumped on a fuel pressure issue.
Gets 32 psi at idle and drops when I give it throttle. jumps up to 40 psi if I remove the regulator vacuum line or run the fuel pump through the diagnostic port.
Pressure doesn’t increase if I pinch the return line.
Getting 9v at the fuel pump but doesn’t drop with throttle , pulled the efi fuse and it was melted.

I’ve replaced the tps, fuel regulator, fuel pump (twice), fuel filter and the efi fuse.
Any help is appreciated

 

[84Prerunner]

Your pump can’t supply enough volume to keep up with rise in RPM. 9v is pretty low, can you rig up a jumper to supply a full 12+ v? Betting that helps a lot.

 

[smokeysevin]

Does this model have that weird fuel pump resistor setup?

If it does, the resistor could be bad or it could be the relay that switches it between full power and the resistor.

Sean

 

[GilbertG]

Your pump can’t supply enough volume to keep up with crude in RPM. 9v is pretty low, can you rig up a jumper to supply a full 12+ v? Betting that helps a lot.

This was it thanks man. One of the butt splices wiggled itself loose.