Hey guys... So long story short, setting up a Nitrous Outlet Promax kit in my cousins 09 base ls3 a6 car. I know the typical norm for nitrous on these cars is to run a stand alone fuel cell dedicated to the nitrous but we wanted to future proof for the next phase of the build (boost) so we went with an ECS stage 1 a1000 Aux Fuel Pump kit. Typically the trigger for this kit is obviously a hobbs switch that comes on when it senses positive pressure. Unfortunately being N/A positive pressure is something we wont have. I've purchased a vacuum opperated switch which I think will work and have it wired in series with the arm switch for the nitrous so it will only activate when the system is armed. We haven't had a chance to test it though and im not sure how sensitive it will be or if it will work at all. Right now I have it plumbed directly to the port on the back of the intake, the switch in question has a set screw to adjust where it comes on but no real instructions on how to set it up (I believe it was originally for a transmission solenoid circuit). We're going to try to test it here in the next few days however I wanted to see if anyone else here had any other ideas in which we could use to trigger the pump to come on under load when the nitrous is armed. I debated trying to figure out a way to do it with the TPS signal but I couldnt find any type of stand alone way to do it. Would love to hear some other input or ideas.

 

You could trigger it by way of a relay using a TPS or window switch, but why not just wire it through a relay so that it switches on when you arm the nitrous system. You won’t (shouldn’t) see any increase in fuel pressure at idle when you turn it on, so doing it that way won’t affect anything, and if you’re like me, you’ll only flick that switch on when you reach the startline anyway? The added benefit of that is that when you arm the nitrous system, you’ll be able to hear the aux pump turn on. It’s also the simplest and cheapest way to do it, imv.

 

That was my initial thought as well but ECS told me I would have to worry about heating up the fuel in that case. Seems like the most simple solution. Only thing I can think is maybe having it on a secondary switch for times when I'd want to arm the system and not the pump (tuning the promax so it doesnt sit running the whole time im making adjustments)