Engine quit after 3 to 4 blocks, 3 times on the way home, made it to garage with relief.... no AAA this time.
T/S: Starter and cranking normal
Jumped fuel pump from battery - fuel pump running
With ignition on (3): no fuel pump with transmission selector in D or R... Also no fuel pump when reaching into AFM and moving flap
With ignition on (3): white wire at fuel pump relay has 12 volts
By jumping White/green wire at fuel pump relay with 12 volts from battery, have fuel pump running
Just to speed T/S, installed spare main & fuel pump relays and spare CTS sensor. no change

I am suspecting Diode Pack as it is in common with all feeds to fuel relay
Any thoughts from group as to what I am missing
Thanks in advance
Rgds
David

 

It could be the diode pack as it supplies then12V to the fuel pump relay from either the cranking or AFM

The fuel pump relay coil is earthed through that set of grounds that are bolted to the manifold. This is a common problem area so I would start there by cleaning up the connections.

 

Andy
All is well with two good road tests. Not 100% sure of fix, as I chased wires and connectors with multi-meter. Clean many connectors, change some easy spare EFI relays, CTS and R/H fuel qty sender. Could have been a self-induced problem. I opened diode pack and check all internal components, they all check good.

After new fuel qty sender "I put 11.5 gallons in tank" ???? I may have have just ran tank too low, and was getting air in system as I accelerated and the fuel sloshed. New sender was $39 from Moss with new ring and seal. R & R in 20 minutes and now reads properly at full, will check calibration at 3/4s, 1/2 & 1/4.
Good to be back on road, but do miss the 100% certainty of finding a fault.
Rgds
David

 

On engine start, the direct feed to the pump relay is closed following relaxation of the ignition key from "Start" to "Run". The AFM now takes over volts supply to the pump relay via two tiny contacts inside the AFM, that are closed when the flap moves with induction of air into the engine. In testing, you correctly pushed in the flap with the ignition switch in the "Run" position, which should close those contacts and supply volts to the pump relay, but did you check volts were actually getting to the relay ? I had a helluva load of trouble with a 1980 XJ6 on this very problem, only alleviated when I removed the black cover on the AFM, and cleaned the contacts. I also "repositioned" the contact holding wands so a more firm contact was made. I had no further trouble after that.