ok guys... i've had the 3.5 swap done for about 2 months now and i have finally decided to upgrade from stock fuel pump to a walbro.

all this time, with the stock fuel pump, it was running a consistent 38-39psi fuel pressure, and now that i put the walbro in, it bounces from 46-50psi up and down consistently, and it does not stay still....i adjusted the AFPR (SARD not ebay) and it does not change.
When gas pedal pushed all the way down, gauge maxes out, then it drops back to bouncing 46-50psi and when driving, i feel a huge power loss around 4k rpm +, car does not want to move.

thinking about putting the stock pump back on...
is the walbro a must for the swap for tunning or will it not matter?
thanks......

Peter

 

http://forums.maxima.org/showthread.php?t=481393

 

Peter, you have a 97, means that on your fuel pump circuit, you have some "fuel pump voltage drop resistor" junk. Streetzlegend explained it to me something like "at idle closed loop, it drops the voltage to the pump [god knows wat for] and as the rpms come up, it increases the voltage. When its disconnected and grounded somewhere else [it works on the ground circuit] it provides the pump full voltage". You may want to contact him about it for further insight.

 

Oh really.... ill get a hold of him... thanx for the help!

 

How are you controlling your VI? RPM switch?

 

Excuse me sir, what does VI have to do with fuel pressure?

and no, he doesnt need a way to control a so called "VI device"... if you read bet'n the lines

 

Nothing. He said he felt a huge power loss after 4k. If he's using an RPM switch to control the VI it's closing around that RPM instead of opening up.

 

ahhh jez. tis is tr00f.



But yea, no need to control anything there :-X