first of all.. will 9v turn on a standard 12v automotive relay or does it have to be 12v? second, the resistor has a wire running to it from the ECU to the relay part of it, when that wire is 12v does it open or close the resistor. in other words, is the wire from the ECU 12v at idle or at WOT??

9v might turn it on, i think it prolly would. i dont know the answer to the other question but it would be easy to check with a test light or voltmeter

yeah it would be ez to test.. unfortunately my car wont idle and my resistor relay is messed up i think.. can someone test this plz. thanks guys.

your fuel pump has a resistor box as well, it limits the voltage to the fuel pump and then at WOT it opens up to a full 12v.



as for your injectors they should stay at a constant voltage



you say the car will idle so its starting. if it was your injectors most likely the car wouldn't start because the injectors would be fireing properly

i dunno how this has anything to do with what i was saying. but i am not doing this to fix my idle problem. this is just something i want to know. im not talking about the wire running to the fuel pump.. i know what the relay/resistor is.. thats why i am posting about it lol. a wire runs from the ecu to the relay/resistor, i wanna know if thats 12v at idle or what. im pretty sure its the green/red wire on an S4 TII. just wanna know if its 12v at idle or 12v at WOT. thanks.

Well lets just take a look...

http://devilmotorsports.com/forumpics/fuelpump.gif



http://devilmotorsports.com/forumpics/ecu.gif

sorry but i dont think this tells me WHEN the ecu is pushing 12v to the resistor/relay. i see nothing pertaining that.. i know how its setup.. i wanna know if the ecu pushes 12v on the green/red wire at idle or at wot.

my car pushes 12v at idle when i tested from there. Belive it hits around 14 at wot

woops that was me ^ roomate was signed in on my comp

14v on the green/red wire running to the relay on the resistor/relay for the fuel pump? or 14v to the blue power wire powering the fuel pump?