What is this electrical vacuum device? - 1985 720 with Z24

[spddm0n]

Hi all - 

I just purchased a 1985 Nissan 720 King Cab 4X4 pickup and I'm working to get all the vacuum lines routed correctly and rebuilding the carburetor in order to pass emissions here, and I can't find any good diagrams to identify this device sitting on top of the inner fender liner (apron) inside the engine compartment, nearly underneath the silver data plate (attached to the passenger-side engine bay sidewall), and sitting on top of a small platform that is bolted to the sidewall.

I've seen a variety of other trucks and photos of other trucks and none of them seem to have this device. I Googled the numbers printed on the side of the electrical device, but nothing conclusive comes up.

Anybody know what this is and what the correct route of the vacuum lines should be?

Thanks!!
 

 

 

 

 

 

 

 

[720_Jeff]

I've never seen one of these on a 720.  It sure looks a lot like this on ebay

 

https://www.ebay.com/itm/90-96-Nissan-300zx-16s-EGR-solenoid-valve-cut-off-switch-twin-turbo-1495640P00/303125086145?hash=item4693a9bfc1:g:jlAAAOSwIUFbW56~

[spddm0n]

Holy Moly!!!  That's exactly what I have on there!  Not the exact same number stamped into the body, but !

 

Is this device not an OEM part on the 85 720 (Federal emissions - I think that's what mine is)? 

 

I wonder if the previous owner installed this to try and improve emission output?  I think my EGR valve is shot anyway, but if this device is not intended to be there, that simplifies my effort to find how the vacuum lines run to it. 😉

 

Hers's a pic from the eBay ad (for long term reference).

 

[spddm0n]

On the other hand (duh!), there is a connector on the factory wiring harness for this device, so it must be an OEM device.

 

I traced the wires in the electrical connector to two different pins in the 6-pin electrical plug that connects to the carburetor (connecting the anti-dieseling solenoid and the Air/Fuel ratio solenoid) and to a relay bolted to the inside of the passenger fender, near the front of the vehicle (near the radiator support).

 

I found a wiring diagram that I believe is for this vehicle, and it looks like there is a device called a High Altitude Solenoid.  That would make sense if this vehicle was originally shipped to this location, here in Colorado.

 

I'm going to have to keep looking for the vacuum diagrams that include this device. 🙂