I think I need a new Fuel Pump .
 

well I seem to be having some fuel issues ..

first a little back story so you know where I'm at

I replaced my fuel pump about 6 months ago. it was a Walbro 255 ( I discovered maybe this wasnt the best idea after ) as I read they go bad


so a couple months ago I realize my car starts to go lean . on WOT so I sit it down have a talk with it and we agree that we'll take it easy for a bit .

I thought well the fuel pump is new .. But the injectors are 20 years old , as it only has issues after the secondaries come on maybe my secondaries are having problems .. ( I was running at 100% injector duty ) , so I decided to replace my secondaries with 1300's

after I did I hadnt had a chance to give it a go last week until we were at a dyno session .. and it started to go lean past 4k rpms ( when my secondary turbo switched on ) I went into the power FC and I richened everything above 4k rpms and we did a slow pull and again past 4k rpms it just starts to go lean .. same place even after added a ton more fuel , and injector duty being at 85% running 13 psi vs 70% injector duty I had it before . WITH METH ..

so I'm starting to think I got a bad roll on my Walbro .. and because I was in a hurry the day i got it and got it from a local performance shop they told me that they only warrantied the pump if I installed it with them ..

Now about the installation .. the Wiring was been replaced . I have very good power going to the Fuel pump. I know FD's had issues with fuel pump wiring . so I redid mine when I was building the car.

I'd like to keep the stock like wiring system . which is why I dont want the aeromotive one where you need to redo the wiring .

so

WHAT are my options ... for Good fuel pumps that can support 400 WHP

and what are your guy's recommendations and opinions . '

I heard there was a new Walbro FP that was really good? , or the Supra pump? or the bosch pump?


*Ps* I know there are tons and tons of threads on fuel pumps its not that I'm being lazy its just ... there are just SOMANY its hard to filter out the ones that relate to my certain perdicament.

Have you checked the fuel filter? When you say you rewired your pump did you use a relay? Apparently my old FD went lean after the relay got hot (used the wrong relay). So my fuel pressure would drop off.

You say it's going lean, have you checked the fuel pressure when this happens?

yes I used the same relay I dont think its the relay I checked all the relays and it happens regardless of how hot or cold it is

all I did was replace some of the old wiring and tested the Voltage at the pump . and it was very good . new connectors , everything is done right . My dad's an electrical engineer . and he helped me do the electrical stuff on the car . as far as electrics go my car is in very good condition

Fuel Filter is also new . Fuel tank was also cleaned

Get a supra pump. (I think the walbro is failing)


Verify you have at least 12V at the fuel pump (remove and check at terminals)
Change fuel filter.
Check for clogged/damaged lines.
See if you can install a fuel pressure gauge and watch it while driving to make sure you have proper fuel pressure.
Check vacuum line to FPR.

www.rx7.com sells a competition pump that flows a bit more than the Supra pump. IRP installs them on almost all 400 rwhp builds.

Ok now just a random question .. Can my fuel pressure regulator go bad I'm honestly at a loss as to how the inner workings of this apparatus is .

People keep telling me I need to adD a FPR but I'm wondering if there is any chance that my sotck FPR went bad.