I just wrote a reply to a simular question... I'm not the expert but thinking back after having replace the fuel pump relay which was done in (overheated) due to intank pump rubber hose giving way (rotting away) and over working main pump causing relay to overheat. In the end the relay and intank pump were problems but the problem that lurked for 6 months till I finally ran it down was the bulkhead connector at rear fire wall, it carries the voltage from the ballast resistor to the coil... this connector as well as other connections in the same bulkhead where intermitant, I suspect the one suppling the coil voltage was the most bothersome because if the coil stops firering then the fuel relay drops out because it relies on a signal from the ignition system (much like the tach feed) to tell it (the relay) that the engine it turning. They don't want the pump running if the motors not). In my case I had a tach (comes with turbo cars) and the tach would drop to zero even if I left clutch in and motor was spinning. think thats because the same pump relay also supplies voltage to the ingnition system and once the relay drops out because of a intermitteant signal to the coil then the ingnition drops out also because its voltage is supplied by the same relay - tach is obveously on the same feed from this relay. Thats why car will not restart till switch is shut off then turned back on .. its a latching relay. I got pretty good with jumping this relay or shutting the switch off then restarting.. in traffic this started to anoy me as well as drivers following me ... some body ought to write a good test procedure out .. or make up a good diagram showing the path and fixes.. certainly none of the manuals I used where any good in this area but then never owned or saw a bently manual which is susposed to be good. And lastly this same car did have a nast habit of quiting going around a corner .... never really could answer exactly why but problem grew worse and I didn't need to go around a corner ... could just have been that bulkhead connector with a slight change in G force which changed connection to an open... only has to mis one beat and that relay will UNLATCH. hope this helps