Explorer EFI Fuel lines

[450rbronco]

The little schrader-type valve at the front right (that has a little black nub from the factory)? I believe most guys attach a pressure gauge there to monitor their pressure (at least based on the pictures i've seen). WH and others sell a gauge that I plan to mount on mine.

No the part on passengers side rear that looks like it has a nipple on top for a vac line or something. Can’t temper from when I pulled the engine.


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[1buckeyefan1]

No the part on passengers side rear that looks like it has a nipple on top for a vac line or something. Can’t temper from when I pulled the engine.
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Ah, good question.. i just cleaned mine up the other day and wondered myself where I put the part that connected to it.. and now I realize i'm in the same boat as you. Hopefully garberz, 904bronco, or someone further along can chime in and enlighten us I did find my 'before' picture and the part though.

According to a Broncobowsher post back in 2011, it's a Pulse Damper. I can't do any better than him, so here was his explanation:

The retrunless also adds a pulse damper to the fuel rail. It is the thing that looks like a fuel pressure regulator but isn't. What it does is act as an accumulater so when an injector fires the whole mass of the fuel in the fuel line doesn't have to start moving. Also when the injector stops it acts as a bumper so the fuel pressure doesn't hammer the system.

Why returnless? There is a little cost savings in only running 1 fuel line, also less potential for leaks. But the biggy is emissions. A return style dumps hot fuel back into the tank. That wants to vent as vapor. If you keep the tank cooler it is easier to control evaporative emissions. We did a lot of testing of this stuff back in that time frame.

 

[1buckeyefan1]

So I found my vacuum line for the Fuel Pulse Damper (FPD).. picture attached

It shares a vacuum line with the EGR and hooks to the upper intake. For those that have deleted the EGR, have you simply plugged the extra port?

 

[1buckeyefan1]

Made some progress this week:

Got a hole cut into the NWMP tank.. the biggest pain was trying to get exactly (16) 3/16" holes that fit into the backing plate w/out the bolts binding. I ended up making them 7/32" and figured the gasket could do the rest.

I also combined the PA-2 with the Explorer in-tank regulator. I had to modify the mounting arm a bit and have it discharge through the rear, but to my untrained eye, it should work almost as well as a factory Explorer pump?