How to wire the MAC boost solenoid to EMU

[rockyboist]

I had it come in a pnp adapter but it isnt working so I'd like to wire the solenoid directly to EMU, there are 2 wires in it and I know it doesnt have the polarity so it doesnt matter which one goes into what.

Question is where to connect these 2 wires.

1 wire goes to EMU Output (G4 in my case)
1 wire goes to the 12v fused power supply or to a ground?

I dont want to fry anything so I'd like to be careful.

Thanks in advance.

[ihiryu]

shoudl go to 12v power. You want to put a flyback diode in place.

[Scooter]

What is the reason for the flyback diode? Does it go in parallel with the solenoid?

[pric]

When the solenoid is switched off, the field of the coil is breaking down, which creates a voltage spike, that voltage has switched polarity.
This voltage could damage the voltage source(e.g. the emu), and or powering it thru the output.

You have to connect it anti-parallel to the source.

[Kisielisodd]

for mac valve it is not necessary to ad flyback diode EMU will handle it without.

[Scooter]

Could you please elobrate? Do all mac solenoids have a builtin diode, or just certain models. -thanks

[ren]

There's not a built in diode in the Mac valve but the amount of back EMF is not enough to worry about, unlike something like a VVT solenoid.

[WHPZach]

High current, high frequency solenoids are what necessitate flyback diodes. A boost control solenoid doesn't use enough current to necessitate a flyback diode, nor does it run at a high frequency.

[kawaman]

for mac valve it is not necessary to ad flyback diode EMU will handle it without.

Can a boost control solenoid on 20- 30Hz be driven by stepper motor output ?

its a pierburg valve form VAG , or vauxhall.

part number : 7.00470.07.0
they are crazy cheap like 25 -30 euro's FEP connector is like 3euro, and work perfect for simple bleed boost controll.