runnermedic

98 4r limited with 4.56 gears no cel light,the only issue is that im not able to read codes because the fuel pump keeps priming and not turning off in a few seconds,well i figured out testing with another ecm and the fuel pump keeps priming,so maybe the fuel pump is not making enough pressure that's why it keeps priming. the surging is present only going uphill around 2000-2500 rpms and take off seems to be a little sluggish sometimes. could it be possible that the fuel pump is going south? the PO installed a 4 cylinder fuel pump assembly (a tacoma one for sure fuel sender is different)
i read somewhere here that the v6 fuel pump is rated at 90lph 43psi dunno about the 4cyl one.
maybe the 4cyl fuel pump is weaker?
clogged cat converter?
no ping
maf cleaned
tb cleaned
no vac leaks
injectors ok
wiring and relays ok
new plugs and wires (oem)
seafoam treated twice
new fuel filter
coils ok
fuel pump connection and wires ok

if the fp is going south then which one will be a better option denso,walbro airtex?