Supra Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
601 Posts
Discussion Starter #1
I have 3 walbros running in my tank. 2 currently wired in. I just started the car for the first time and realized that at idle I couldn't raise the fuel presure over 30psi. It seemed that the pumps were not pumping what they should. BTW I am using the stock fuel computer. I just checked the voltage across the pumps and it was only 3 volts. I guess the fuel computer controls pressure by varying the speed of the stock pump. I always thought it ran full out and the stock fpr took care of it.

Anyone else notice this as well?

I plan on running a relay now with a trigger off the ignition switch.
 

·
Registered
Joined
·
601 Posts
Discussion Starter #2
I just wired in the relay. After about 15 seconds it gets really loud as the return fuel starts spitting back into the tank. Kinda freaky sounding. But now I can adjust the pressure to what ever I want. What is the typical for Sard injectors. I heard 35. They seem to make a strange sound above that. Oh ya when I kill the pumps the car still runs for 3 min just on the pressure alone. It drops about 1 psi every 15seconds at idle. Kinda cool.
 

·
Registered
Joined
·
1,418 Posts
it shouldn't be 3 volts, should be closer to 9v, and then go to 12v's at wot.....bypass the fuel pump resistor, and that should give you 12v's to the pump.......i'd probably just run new wiring to the pump anyways, with 3 pumps, you'll need heavier gauge wire and a relay because of the increased current draw.
 

·
Registered
Joined
·
1,418 Posts
do you know where the fuel injector resistor is? it's on the OPPOSITE side of that, i BELIEVE the passenger side, and it looks exactly like the fuel injector resistor (big heat sink). it should have only two wires, an IN and an OUT. just unplug it and jump it with some thick gauge wire temporarily and see if that helps.
 

·
Moderator, l337 M0d3r4t0r
Joined
·
12,246 Posts
yes you need a seprate line wire use the stock line as teh 12 volt trigger, if you have a sound box, you can steal power off the feed wire if it's a large guage.
 
1 - 6 of 6 Posts
Top