So I finally got a decent fuel pressure gauge installed with no leaks and was able to monitor until it stalled and died. This is after I went ahead and pulled out the tank, which I've been meaning to do for years anyway. No rust, varnish or sludge, although the return banjo had some gunk lodged in the outlet. Checked all of the fittings, hoses, relief valve, etc. Purged the hard lines with carb cleaner and a few blasts of dry shop air. Tested current to the fuel pump, which was right at 12.8 volts continuously. All good.
After a couple of hard starts to get the gas flowing back into the engine, the car idled fine for a while with fuel pressure right at ~35psi. Then it started to drop rather quickly, maybe over about 30 seconds, to around 20 psi, whereupon it stalled and died. So I started it again, and the pressure would only increase if I pulled the throttle, before dropping again. I tried pinching off the return hose from the regulator with a pair of vice grips, with no noticeable change. Stall.
The fuel pump is new, after the original one seized after a prolonged stay in the garage. But what else could it be? I swapped three different combo-relays with no difference. Spark is strong. Battery is new. Current to the pump is full strength and consistent. Fuel filter is new but I'm going to swap one from the parts shelf, just to see what happens. Maybe it's waterlogged.
as good as a car can be... briefly.
Last edited by chairmankaga; 03-27-2017 at 08:22 AM.