Fuel Pressure cuts out intermittingly at idle - comes back after 20 minutes

Hi All. I've posted before, with no solutions, but now I have more information. I have a 98 Cobra. I have two open issues on the car. Anyone ever have a situation where you turn the key and the car kinda makes a pop sound and just goes completely dead electronically? All I have to do is disconnect and reconnect the battery to get it back. It might start normal or do it again. Eventually, it'll start just fine and then run like it never happened. That aside the bigger mystery is this issue I'm having with fuel pressure. The car will run normal and great. no issues driving, no issues WOT. Then randomly, at idle and only at idle, the car will just cut out. I was able to verify that it has spark still when cranking, but the fuel pressure is gone. down to about 3 psi. On attempts to restart, the usual fuel pump prime sound has, in the past, not happened at all until it comes back when it feels up to it. This last time, i heard something under the hood, a different sound, like a relay or something is trying to energize the pump, but still no fuel pressure. Given a rest period, it comes back to life. 30 psi on prime (with a more robust sound under the hood), starts like nothing ever went wrong. Forscan is showing no codes at all. This has only ever happened with the car was idling. it's not repeatable, there are no common circumstances when it happens and it has, so far, always been fine after a 20+ minute rest. this is a garage kept car. never driven in snow, rarely ever driven in rain. This happened about 8 years ago and I swapped in new OEM fuel pump and it ran fine for another 8 years, but something in me just doesn't feel like it's the pump as it never hiccups at all when driving and always comes back after a rest. I haven't been able to catch it in the act where I can then go connector by connector in a diagnostic, but if this sounds familiar to anyone, suggestions would be welcome. THANKS!

Thanks for the reply. Sounds logical. I'm picking up an electrical shop manual to get a handle on the whole circuit for the fuel system

Thanks for your reply. A few years ago, I put in a quick disconnect on the positive battery cable since this car sits all winter and I feel something related to this has something to do with the pop car dead issue. I think the best thing to do is replace that cable, which feeds power to two different parts, as I don't need the disconnect anymore since I put in a storage charger. However, I can't think of how this affects the fuel pump given the car can crank over and has spark, which are high demand draws when it's not running. what is shutting the fuel pump down, only ever at idle and requiring a 20 minutes rest before it'll come back on line is just baffling. and over the course of about 500 miles this summer, it only happened 3 times and completely at random. just so odd

Thanks. I have a forscan scanner and all systems register perfectly normal when it's running. if I knew I could repeat the issue, I could be watching it, but it's running normal one second, the next, it's gone and then comes back on like nothing happened and could operate fine for weeks. it throws no codes. However, I'm putting in a new battery cable. I just ordered it. cheap part to at least eliminate one possibility. The car is garage kept, so all the wiring looks great, but I also ordered shop manuals and i'm going to do a comprehensive check of all connectors related to the fuel system.

Thanks. I'm going to check the charging system thoroughly and with a new cable, maybe there is some hope.