I am in the process of seting up a custom surge tank setup for my build.

I will be utilizing a Weldon 2025 with speed controller to feed the rail and I am trying to figure out the best way to setup the wiring.

Weldon 14000 Pump speed Controller



This device uses a potentiometer to slow pump speed at at engine idle. It also has a "race" mode which allows the pump to go to full speed when needed. This is accomplished by closing the circuit (brown and black wire) via a "switch".

The switch or circuit can be closed a few different ways. The most common being a Hobbs/Boost switch, or ECU controlled.

That being said I would like to use the ECU to close the circuit and put the pump in race mode. To put the Pump in race mode, the controller needs to see a 12 volt signal going to the race terminal.

Here are my thoughts on doing this so far:
We know that the ECU uses TPS and load to determine when to kick the OEM pump from 9 to 14 volts (thanks Bryan). What I would need to do is take that signal and run it to a relay that could either provide 0 or 12 volts to the race terminal on the speed controller. No varying voltage can run to the controller or pump.

So would it be possible to take that signal from the ECU and convert in in to a relay providing 12 volts to that terminal?

What we would need to do here is take a signal form the ECU Fuel pump
relay:

Pin 96 is FPR#2

Pin 51 is FPR#1

Correct? Which one? Also voltage input to the relay is believed to 5v. Some how We need o take this 5 volt signal from the appropraite wire and tell is to trip a relay providing 12v to the race terminal.

Wiring Gurus help me out here. Thoughts?


Thanks to Bryan, Clipse, and Frankiago for the info so far.

 

I don't want to go off-topic here.. but I don't get this thing? Their FAQ says it is a PWM controller (nice, no heat from resistance) but it uses a potentomiter too (that doesn't really make any sense).

I guess what I'd have to ask is... whats the point? It can't raise voltage above input.... so what is this thing getting you that the factory setup doesn't provide?
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That now said: I'm not sure which wire, but I'd love to find out. It shouldn't be very hard to test the voltage going to either, and if putting WOT TPS flips it (without any load) then that should be easy to measure... but I'm not sure that is the case.

Do you know where the fuel pump solenoid is? ....those items you listed might actually be for the fuel pressure regulator solenoid.

 

Ok, now bare with me... Since the ECU steps the oem pump up from 9 to 14v anyway, then all you have to do is tap into the normal pump wiring, get a diode that requires 12v, then connect the other end of the diode to the pump switch.

Total investment ~$5

Done. Yes, I am awesome. You may bow to me now.

 

LOL. Thank you for the input.

Im trying to figure out where to tap into. Could you take a look at this?

Fuel pump relay circuit

 

Lomker had one of these I think, wish he was still here

 

I know. I found myself wishing many times this week, that I could talk to him and pick his brain. He is the one who inspired me to go this route. I have read his thread on Mitsustyle a bunch of times now, trying to fiugure out how he set it up.

 

POT is used to set the PWM at idle. It's just a human interface device.

 

How do you think the POT will affect the PWM values entered during tuning? Will this be difficult to tune with?

 

Tap into the <F>2L wire. There are just the 2 wires going to the pump: the ground, and the hot. The hot fluctuates between the 9v and 14v depending on if the secondary relay is active or not.

SOOOO.... If you get a diode rated for enough amps, that requires a 12v signal to arc through it, all you have to do is put one end on the hot pump wire and connect the other to the box. Then PRESTO, the diode won't let ANY voltage through until the wire hits 12v or higher.

It's so simple that it doesn't seem like it'll work, right?

 

why dont you just tap the line going to the fuel pump relay in the engine bay relay box?

or at least back trace that one and then tap it at the ECU...

 

^either way... tap it at the relay or pump. Whatever is closer to where you want to mount the box. If you are going to tap it at the ecu, then you need to make sure it puts out the required voltage.

The point of tapping in after the relay on the pump side is that we KNOW that'll crap out 12v+ when it kicks on.

 

Matt and Tephra, thanks for your help on this. It seems it was one of those issued that I was making out to be way more complicated that it was. Seems like an easy solution. Hopefully this will work the way I plan and we can stay away from a Hobbs switch and have an ECU controlled Weldon

Tephra an especially big thanks to you for all of your hard work and contributions to the community. Much appreciated
Its a shame to see others profiting from your hard work without paying dues or giving credit where it is rightfully due.

 

That would be 1B, correct? If I'm interpreting the diagram correctly that's what I was thinking.

EDIT: I see how the diagram is written now. I misinterpreted ETACS as the ECU. I believe tephra is correct with pin 51.

 

pin 51 on the ECU by the looks of things.

you need to make sure that the Weldom thing only uses that as a signal current, not a load current...

 

^exactly. If it's a load, you could fry the ecu. If it's load you'll def need to tap the pump wire then.