my rb25 killed 4 walbro pump and I still dont know why

[ka24eracer]

I have a 1993 180sx with a s2 RB25det , pretty much stock with only a freddy intake , high mount IC , 3 inches everything .

Since I installed the Freddy intake , it seem like there is a restriction in the fuel system. The pump is moaning instead of whining when new but still able to keep a good fuel pressure . But the pump cant survive for more than 1 week . After a couple ride , I can't get more than 30 psi a the rail ...

Ive tried 4 different FPR , I replaced both complete hard line with rubber efi fuel hose , went through 4 real walbro 255lph , the only parts I didnt replaced are the fuel rail and injectors , but I inspected them and it seem ok.

[l0nestar]

Did you replace the fuel filter?
How is your pump wired up (power wise)? Is it re-wired for full 12v constant voltage or is it still variable (factory)?

[StricNyne]

ya i agree with lonestar, i would hardwire pump, or invest in kennebelle boost a pump (13v, with increasing voltage with boost to around 15v)

[ka24eracer]

IVe tried even without filter ! And the wiring is a relay on the ignition to get direct voltage from the battery

[rb25det250sx]

it is gettin perty hot. check for vapor lock every so often. maybe your just starving the pump.

[ka24eracer]

With a brand new pump , with the pump on and the engine off , the pump is moaning and has a hard time pushing the fuel ....

[raremotive]

Get your multimeter out and measure the supply power...verify that the pump is getting what it needs.

[ka24eracer]

I've tried it with the wire directly on my battery without luck

[RustspecS13]

Are you running with more then 1/4 tank of gas, or are you running on empty?

~Alex

[USMCgetsome]

i agree with the above post on checking your wiring and seeing what voltages you have going to the pump. Post up voltages and grounds. I had the same issue and all my problems ended up being a slowly dying fuel pump. I've heard great things about the hard wiring kits as posted above

[raremotive]

I've tried it with the wire directly on my battery without luck

And... if your ground is bad, how would you know the difference?

[ka24eracer]

You guys we're right !

Everytime Ive tested the voltage I was grounding my multimeters to a near body ground. I had a huge resistance on my stock ground wiring going to the pump. My fuel pump had about 7 V .

Replaced my ground wire and now the car is fine ! The last fuel pump seem to be ok ! The 3 previous fuel pump were obviously melted down .