ok i have an 88 turbo2 and every time i go into boost the fuel psi drops from 40 to passed 20psi i have done every thing could think of i cleaned the fuel tank because it was filled with **** and i changed the fuel pump,fuel filter,add a adjustable fuel regulator,extra fuel pump and after all that the car still drops fuel psi i dont know what 2 do any more heres a list of mods


egr del ,a/c del,ps del
hks fcd
2.5 down pipe
3' exhaust
and thats it the car is all stock i have a greddy emanage im about to put in

 

could be the lines ( not probable since you said it only happens in boost) could be bad boost pressure sensor good luck

 

where are you measuring the fuel pressure?

 

i wouldn't suggest boosting until you find the problem.

Check the lines, possibly a intentional "kink" in the hardlines could assist in building pressure? But find out what the problem is as that is kinda a B.S. solution that would hurt you in the longrun.

 

Hey man, I'm contemplating getting an emanage for my build, let me know how it works out. Sorry I can't lend a hand with your problem :S

 

thanks for the post ed he is talking about my car thanks for in put but still dealing with this prob i replaced pump with a advanced auto pump ?? maybe i need a walbro 255??

 

What are your injectors? Is your stock FPR still in place on the rail?

 

yes i have stock fpr i dont have an aftermarket one he messed up stock injectors

 

the FCs have notoriously shitty electrical systems powering the fuel pump, i have even measured one FC pushing 300+WHP that was dropping voltage to below 6volts under a load. check the voltage at the fuel pump and/or rewire it directly off the battery with it's own relay(note this will affect your emissions if you are trying to keep it smog legal you cannot do this without an adjustable ECU due to it being too rich at idle).

if you want to keep a system similar to the stock one but with a better controller and that can boost voltage to 20 volts and fuel pump efficiency try the keny belle boost-a-pump. i have one customer who is running it and it seems like a decent system, then again he is pushing the efficiency barrier of a supra pump so.. not like he had a choice.

 

ive allready re wired pump with relay 13.6 all the time and i also have a fcd hks

 

update sonininstalled nnewn walbro pump test drove was great boost lil hesitation but think its ad plugs from running messed up and when left garage started droping pressure gain thinking maybe some thing in line blocking so im gonna run two new lines