Yo,
Battery must be fully charged with nd no load should be at least 12.6 volts depending upon meter accuracy.
Did you do this to get the pumps running?
Test & Diagram at the Diagnostic Link Connector in 84-95;
Grounding the FP lead at the DLC will allow the pumps to run continuously with the ignition switch on.
http://www.thedieselstop.com/faq/9497faq/maint/vra/images/a9465b.gif
Anyway, the pumps are working. Is the FP Relay still chattering? If so, check at EEC relay for intermittent battery voltage at White/light blue wire from ignition switch and continuity to ground on black wire to ground G801 On LH inner fender behind headlights.
*** Check that Ground first.***
If intermittent voltage from ignition switch; Switch Pin-Out Diagram & Continuity Testing (Logic Tables in 87-91 (from Factory Manual and the Ford Electrical & Vacuum Troubleshooting Manual (EVTM) by Broncobill78 (Dave) at
http://web.archive.org/web/20110909003616/http://broncozone.com/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=6659
...
If not intermittent, check Yellow wire at EEC relay for battery voltage from fusible Link N.
If ok...
KAPWR is Keep Alive Power at EEC pin #1, Yellow from same Link N
Pin 37 Red wire, Circuit 367 is VPWR -Vehicle Power supply voltage (regulated 10-14 volts)
Did I cover the FP AND EEC Relay Circuits?
Am typing on a cheap tablet and can not scroll back in edit mode. Am editing to add info from "If ok..." to here..
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BTW,
Single-Function Reservoir in 84-89; "...The PN for the filter is given, but you shouldn't actually have a filter in there. It should be an external inline filter further up the frame rail - you only buy the reservoir filter to get the O-ring, and only then if you have some reason to open the reservoir bowl. Unless you're having fuel delivery problems that you've isolated to the reservoir, you should never open it..."
The single-function reservoir (SFR) is used on vehicles with ONE gas tank, like Broncos, vans, & low-trim pickups. The reservoir is always inside the L frame rail beneath the driver's floorpan about 10" behind the frame fuel pump. The 10mm bolt heads are easy to access on the outer face of the frame rail, but some vehicles have a large heat shield that must also be removed...There's not much to the SFR (which is what ALL Broncos of those years have): the '88 version just has the cup & 1 check valve (earlier versions have 2), but it's almost foolproof... the only moving part is the tank-side inlet check valve. The return ports flow freely and are NOT connected to the reservoir. The engine-side supply port is open to the reservoir. To test it, unplug the frame fuel pump, disconnect the engine-side supply (large) line, and cycle the key. If fuel flows out of the reservoir ******, the reservoir is working normally. If not, disconnect the tank-side supply (large) line, and cycle the key. If fuel flows out of the line, the reservoir check valve is probably stuck, or its internal filter is clogged. A reservoir marked "DO NOT REMOVE CUP" does not contain a filter. For a replacement O-ring for the cup, buy a NAPA 3268 (or equivalent) filter..." by Steve.. Steve deleted reservoir info above from the Broncozone.
For some reason I have not been able to insert pics, except for thumbnails here for a long time since I do not see the icons for pics.