I was just reviewing the process of installing a resistor box for peak hold injectors. Now my question isnt how the injector itself works but how they recieve their signal. According to he install process you clip 4 wires and solder them into one wire going into the resistor box.

Now I'm assuming this is the ground side of the injector? Otherwise all four injectors would open when a signal from the ecu is sent...

 

actually the signal they recieve from the ecu is ground. the wires going into the resistor box are positive. thats why it doesnt matter which yellow/black wire goes where. You cant mix up the ground wires at the injector plugs though. Itll throw off the firing sequence. Id have to look at a diagram, but Im pretty sure most vehicles recieve their signal from the ecu ground.

 

DAMN light bulb. thats right.. I was wondering why the hell you would put a resistor on the ground side.... I'm sure your right