Can't Identify this part

[MustangsMilden]

I hate to be needy but I cannot identify what this part is off of my 86 SVO. It sits in the upper-right corner of the engine compartment by the power brake boost unit. The part number on the blue/gold portion with a vacuum hose connected to it is 'E5ZF-9C408-AA' but I'm not finding any matches on the web. The item to the left is a rubber boot cover Unknown part.JPG with a male, 2 wire connector inside it.




I'm pretty certain the vacuum line connects to one of the larger connectors in the vacuum line rail found along the top of the firewall and that's what I'm trying to verify.

Thanks

[SVOeric]

it's the fuel pump noise reduction 'system' --
basically, it limits voltage to the fuel pump, when not under boost. -- which makes it 'quieter'
I'd be surprised it will run without this, because I don't thin the fuel pump will get any voltage without this plugged in.

the plug for this is up next to the brake booster.

[svono50]

Yep, that is the switch that drops the fuel pump circuit voltage to ~9v at idle and off-boost. I went round and round with this one a year or so ago before simply removing it. The car will run without it, since it is actually it is a 'normally-open'...which means the car would not get full fuel pressure under full boost...ask me how I know! If you remove it, simply create a jumper wire with some flat spade connectors and jump the wire harness connector to give the fuel pump full voltage all the time and call it a day.

The switch is actually adjustable with a small set screw in the middle of its connector spades. It appears when these fail, the switch simply burns out its contacts and remains 'open', therefore defaulting you to lower pump voltage and lean condition under full boost...bad failure mode in my book, but it is what it is.

[MustangsMilden]

Thanks to both for your responses. Not sure why the prior owner had capped the large male connector next to the brake boost one, instead connecting it to one of the smaller connectors in the splitter that was by default originally capped by the manufacturer. Glad I reached out!

[Erics SVO]

Anyone have a good pic of this part installed and pic location of said part/plug?

[svono50]

Since I removed mine, unfortunately not. It laid on top of the brake booster over toward the hood hinge on my car. I think I used the original boot to cover up the jumper I used on it. The pressure line ran over and connected to the manifold on the firewall just behind the upper intake. Let me dig through my pics tonight when I can get to them.

[svono50]

Finally got a chance to look through my pics, no dice, so I grabbed a couple current pics. The switch lived tucked down under the bundle of wires/hoses in the rear corner of the engine bay. I pulled up the cover that now houses the jumper wired I put in the harness connector. The pressure line to the switch was connected to the now capped port in the manifold on the firewall. Hope these help some.

image_46984.jpg image_46985.jpg Switch - Jumper.jpg